Kemper (KMPR) 10-Q1 May 242024 Q1 Quarterly reportFinancial data

Company Profile

Document and Entity Information

Document and Entity Information - $ / shares	3 Months Ended
Document and Entity Information - $ / shares	Mar. 31, 2024	Apr. 29, 2024	Dec. 31, 2023
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Mar. 31, 2024
Document Transition Report	false
Entity File Number	001-18298
Entity Registrant Name	Kemper Corporation
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	95-4255452
Entity Address, Address Line One	200 E. Randolph Street
Entity Address, Address Line Two	Suite 3300
Entity Address, City or Town	Chicago
Entity Address, State or Province	IL
Entity Address, Postal Zip Code	60601
City Area Code	312
Local Phone Number	661-4600
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding (in shares)		64,375,352
Entity Central Index Key	0000860748
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2024
Document Fiscal Period Focus	Q1
Amendment Flag	false
Common stock, par value (in dollars per share)	$ 0.10		$ 0.10
Common Stock [Member]
Cover [Abstract]
Title of 12(b) Security	Common Stock, par value $0.10 per share
Security Exchange Name	NYSE
Entity Listings [Line Items]
Title of 12(b) Security	Common Stock, par value $0.10 per share
Trading Symbol	KMPR
Security Exchange Name	NYSE
5.875% Fixed-Rate Reset Junior Subordinated Debentures due 2062
Cover [Abstract]
Title of 12(b) Security	5.875% Fixed-Rate Reset Junior Subordinated Debentures due 2062
Security Exchange Name	NYSE
Entity Listings [Line Items]
Title of 12(b) Security	5.875% Fixed-Rate Reset Junior Subordinated Debentures due 2062
Trading Symbol	KMPB
Security Exchange Name	NYSE

Condensed Consolidated Statemen

Condensed Consolidated Statements of Income (Loss) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Income Statement [Abstract]
Earned Premiums (Changes in Deferred Profit Liability for the Three Months Ended: 2024 - $19.7; 2023 - $19.2)	$ 1,031.9	$ 1,180.9
Net Investment Income	100.4	101.8
Change in Value of Alternative Energy Partnership Investments	0.4	0.7
Other Income	1.8	1.2
Change in Fair Value of Equity and Convertible Securities	3.4	1.7
Net Realized Investment Gains	6.6	6.4
Impairment Losses	(1.5)	2.1
Total Revenues	1,143	1,294.8
Expenses:
Policyholders’ Benefits and Incurred Losses and Loss Adjustment Expenses (Changes in Liability for Future Policyholder Benefits for the Three Months Ended: 2024 - $6.0 ; 2023 - $1.9)	756	1,052
Insurance Expenses	240.7	269.3
Interest and Other Expenses	59.7	77.4
Total Expenses	1,056.4	1,398.7
Income (Loss) before Income Taxes	86.6	(103.9)
Income Tax (Expense) Benefit	(16.4)	23.8
Net Income (Loss)	70.2	(80.1)
Less: Net (Loss) Income attributable to Noncontrolling Interest	(1.1)	0
Net Income (Loss) attributable to Kemper Corporation	$ 71.3	$ (80.1)
Net Income (Loss) attributable to Kemper Corporation per Unrestricted Share:
Basic (in dollars per share)	$ 1.11	$ (1.25)
Diluted (in dollars per share)	$ 1.10	$ (1.25)

Condensed Consolidated Statem_2

Condensed Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Net Income (Loss)	$ 70.2	$ (80.1)
Other Comprehensive Income Before Income Taxes
Change in Net Unrecognized Postretirement Benefit Costs	(0.9)	(0.5)
Change in Discount Rate on Future Life Policyholder Benefits	141.1	(109.8)
Other Comprehensive Income Before Income Taxes	32.5	76.9
Other Comprehensive Income Tax Expense	(6.7)	(16.7)
Other Comprehensive Income, Net of Taxes	25.8	60.2
Total Comprehensive Income (Loss)	96	(19.9)
Less: Total Comprehensive Loss attributable to Noncontrolling Interest	(1.1)	0
Total Comprehensive Income (Loss)	97.1	(19.9)
No Credit Losses Recognized in Condensed Consolidated Statements of Income (Loss)
Other Comprehensive Income Before Income Taxes
Changes in Net Unrealized Holding (Losses) Gains on Investment Securities with:	(109)	187.2
Credit Losses Recognized in Condensed Consolidated Statements of Income (Loss)
Other Comprehensive Income Before Income Taxes
Changes in Net Unrealized Holding (Losses) Gains on Investment Securities with:	$ 1.3	$ 0

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Investments:
Company-Owned Life Insurance	$ 515.7	$ 513.5
Loans to Policyholders		281.2
Other Investments	213.6	241.9
Receivables from Policyholders (Allowance for Credit Losses: 2024 - $6.4; 2023 - $13.9)	953.1
Deferred Policy Acquisition Costs	595.3	591.6
Total Assets	12,625.9	12,742.7
Insurance Reserves:
Policyholder Obligations	660.9	655.7
Total Liabilities	10,037.2	10,237.7
Kemper Corporation Shareholders’ Equity:
Common Stock, $0.10 Par Value, 100,000,000 Shares Authorized; 64,357,521 Shares Issued and Outstanding at March 31, 2024 and 64,111,555 Shares Issued and Outstanding at December 31, 2023	6.4	6.4
Paid-in Capital	1,852.3	1,845.3
Retained Earnings	1,066.1	1,014.3
Accumulated Other Comprehensive Loss	(335)	(360.8)
Total Shareholders’ Equity	2,589.8	2,505.2
Noncontrolling Interest	(1.1)	(0.2)
Total Shareholders’ Equity	2,588.7	2,505
Total Liabilities and Shareholders’ Equity	12,625.9	12,742.7
Consolidated Entity, Excluding VIE
Investments:
Debt Securities, Available-for-Sale	6,771.6	6,881.9
Equity Securities, FV-NI, Current	230.1	225.8
Short-term Investments at Cost which Approximates Fair Value	520.7	520.9
Company-Owned Life Insurance	515.7	513.5
Loans to Policyholders	280.5	281.2
Other Investments	213.6	241.9
Total Investments	8,764.6	8,904.2
Cash	125.9	64.1
Receivables from Policyholders (Allowance for Credit Losses: 2024 - $6.4; 2023 - $13.9)	953.1	959.5
Other Receivables	195.4	200.5
Deferred Policy Acquisition Costs	595.3	591.6
Goodwill	1,250.7	1,250.7
Current Income Tax Assets	52.6	64.5
Deferred Income Tax Assets	199.1	210.4
Other Assets	479.1	492.6
Insurance Reserves:
Insurance Reserves	5,891.5	6,102.9
Unearned Premiums	1,274.1	1,300.8
Policyholder Obligations	660.9	655.7
Deferred Income Tax Liabilities	61.7	50.6
Accrued Expenses and Other Liabilities	754.8	737.7
Long-term Debt, Current, at Amortized Cost (Fair Value: 2024 - $443.4; 2023 - $—)	449.7	0
Long-term Debt, Non-Current, at Amortized Cost (Fair Value: 2024 - $803.4; 2023 - $1,213.4)	940.1	1,389.2
Variable Interest Entity, Primary Beneficiary
Investments:
Debt Securities, Available-for-Sale	1.7	1.7
Short-term Investments at Cost which Approximates Fair Value	4	2
Cash	0.8	0
Receivables from Policyholders (Allowance for Credit Losses: 2024 - $6.4; 2023 - $13.9)	2.7	0.7
Deferred Policy Acquisition Costs	0.6	0.1
Other Assets	0.3	0.1
Insurance Reserves:
Insurance Reserves	0.7	0
Unearned Premiums	3.1	0.5
Accrued Expenses and Other Liabilities	0.6	0.3
Life and Health \| Consolidated Entity, Excluding VIE
Insurance Reserves:
Insurance Reserves	3,294.3	3,422.4
Property and Casualty \| Consolidated Entity, Excluding VIE
Insurance Reserves:
Insurance Reserves	2,597.2	2,680.5
Equity Method Limited Liability Investments \| Consolidated Entity, Excluding VIE
Investments:
Equity Method Investments	215.2	221.7
Alternative Energy Partnership Investments \| Consolidated Entity, Excluding VIE
Investments:
Equity Method Investments	$ 17.2	$ 17.3

Condensed Consolidated Balanc_2

Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Fixed maturities, allowance for credit losses	$ 7.7	$ 8.2
Receivables from policyholders, allowance for credit losses	$ 6.4	$ 13.9
Common stock, par value (in dollars per share)	$ 0.10	$ 0.10
Common stock, shares authorized (in shares)	100,000,000	100,000,000
Common stock, shares issued (in shares)	64,357,521	64,111,555
Common stock, shares outstanding (in shares)	64,357,521	64,111,555
Consolidated Entity, Excluding VIE
Fixed maturities, at amortized cost	$ 7,562.1	$ 7,565.8
Fixed maturities, allowance for credit losses	7.7	8.2
Equity securities, at cost	210.2	209.3
Receivables from policyholders, allowance for credit losses	6.4	13.9
Long-term Debt, Current, at Amortized Cost, Fair Value	443.4	0
Long-term Debt, Non-Current, at Amortized Cost, Fair Value	803.4	1,213.4
Variable Interest Entity, Primary Beneficiary
Fixed maturities, at amortized cost	1.7	1.7
Fixed maturities, allowance for credit losses	0	0
Receivables from policyholders, allowance for credit losses	$ 0	$ 0

Condensed Consolidated Statem_3

Condensed Consolidated Statements of Cash Flows - USD ($) $ in Millions		3 Months Ended		6 Months Ended
		Mar. 31, 2024	Mar. 31, 2023	Jun. 30, 2023
Net Income (Loss)		$ 70.2	$ (80.1)
Adjustments to Reconcile Net Income (Loss) to Net Cash Provided by Operating Activities
Net Realized Investment Gains		(6.6)	(6.4)
Gain (Loss) On Asset Impairment Charges		1.5	(2.1)
Depreciation and Amortization of Property, Equipment and Software		11.4	11.9
Amortization of Intangibles Assets Acquired		3.2	4.3
Income from Change in Value of Equity and Convertible Securities		(3.4)	(1.7)
Receivables from Policyholders		4.4	(57.4)
Reinsurance Recoverables		1.8	4.1
Deferred Policy Acquisition Costs		(4.2)	(15.9)
Insurance Reserves		(69)	(21.8)
Unearned Premiums		(24.1)	73.6
Income Taxes		26.9	106.2
Other Assets and Liabilities		25.3	(9.6)
Net Cash Provided by Operating Activities		43	5.2
Cash Flows from Investing Activities:
Proceeds from the Sales, Calls and Maturities of Fixed Maturities		323.2	154
Proceeds from the Sales or Paydowns of Investments:
Equity Securities		13.4	19.5
Mortgage Loans		34.1	18.6
Other Investments		3.5	2.6
Purchases of Investments:
Fixed Maturities		(286.9)	(293.3)
Equity Securities		(3.1)	(13.2)
Real Estate Investments		(0.2)	(0.2)
Mortgage Loans		(27.4)	(13.3)
Other Investments		9.6	4.7
Net Sales of Short-term Investments		2.4	0.7
Acquisition of Software and Long-lived Assets		(15.3)	(10)
Settlement Proceeds from Company-Owned Life Insurance		4.9	0
Other		0.3	1.1
Net Cash Provided by (Used in) Investing Activities		39.3	(138.2)
Cash Flows from Financing Activities:
Proceeds from Policyholder Contract Obligations		25.5	89.3
Repayment of Policyholder Contract Obligations		(20.6)	(90)
Proceeds from Shares Issued under Employee Stock Purchase Plan		0.9	1
Dividends Paid		(19.5)	(19.4)
Other		(6)	0.3
Net Cash Used in Financing Activities		(19.7)	(18.8)
Net increase (decrease) in cash	[1]	62.6		$ (151.8)
Cash, Beginning of Year	[1]	64.1	212.4	$ 212.4
Cash, End of Period	[1]	126.7	60.6
Cash (paid) received during the year for:
Interest		(20)	(24.8)
Taxes		(10.4)	(124.7)
Operating Leases		(5.7)	(6.1)
Non-Cash Activities:
Right-of-Use Assets Obtained in Exchange for New Operating Lease Liabilities		0.9	1.4
Equity Method Limited Liability Investments
Adjustments to Reconcile Net Income (Loss) to Net Cash Provided by Operating Activities
Income from Change in Value of Alternative Energy Partnership Investments		(6)	(0.8)
Alternative Energy Partnership Investments
Adjustments to Reconcile Net Income (Loss) to Net Cash Provided by Operating Activities
Income from Change in Value of Alternative Energy Partnership Investments		$ 0.4	$ 0.7

[1] 1 Includes amounts attributable to Kemper Reciprocal reported as non-controlling interest.

Consolidated Statements of Shar

Consolidated Statements of Shareholders’ Equity - USD ($) shares in Millions, $ in Millions	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	AOCI Attributable to Parent [Member]	Noncontrolling Interest
Beginning balance (in shares) at Dec. 31, 2022		63.9
Beginning balance at Dec. 31, 2022	$ 2,670.6	$ 6.4	$ 1,812.7	$ 1,366.4	$ (514.9)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income (Loss)	(80.1)			(80.1)
Other Comprehensive Income (Loss), Net of Tax	60.2				60.2
Cash Dividends and Dividend Equivalents to Shareholders	(19.4)			(19.4)
Stock Issued During Period, Value, Employee Stock Purchase Plan	1		1
APIC, Share-Based Payment Arrangement, Increase for Cost Recognition	15.6		15.6
Equity-based Awards, Net of Shares Exchanged (in shares)		0.1
Share Based Awards Net Of Shares Exchanged	(1)		(0.4)	(0.6)
Ending balance (in shares) at Mar. 31, 2023		64
Ending balance at Mar. 31, 2023	2,646.9	$ 6.4	1,828.9	1,266.3	(454.7)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income (Loss)	(80.1)
Beginning balance (in shares) at Dec. 31, 2023		64.1
Beginning balance at Dec. 31, 2023	2,505	$ 6.4	1,845.3	1,014.3	(360.8)	$ (0.2)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income (Loss)	71.3			71.3		(1.1)
Other Comprehensive Income (Loss), Net of Tax	25.8				25.8
Cash Dividends and Dividend Equivalents to Shareholders	(19.5)			(19.5)
Stock Issued During Period, Value, Employee Stock Purchase Plan	0.9		0.9
APIC, Share-Based Payment Arrangement, Increase for Cost Recognition	12.2		12.2
Equity-based Awards, Net of Shares Exchanged (in shares)		0.3
Share Based Awards Net Of Shares Exchanged	(6.1)		(6.1)
Other Changes in Non-Controlling Interest	0.2					0.2
Ending balance (in shares) at Mar. 31, 2024		64.4
Ending balance at Mar. 31, 2024	2,588.7	$ 6.4	$ 1,852.3	$ 1,066.1	$ (335)	$ (1.1)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income (Loss)	$ 70.2

Consolidated Statements of Sh_2

Consolidated Statements of Shareholders’ Equity (Parenthetical) - $ / shares	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Statement of Stockholders' Equity [Abstract]
Dividends paid to shareholders per share (in dollars per share)	$ 0.31	$ 0.31

Condensed Consolidated Statem_4

Condensed Consolidated Statements of Income (Loss) (Parenthetical) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Income Statement [Abstract]
Changes in deferred profit liability	$ 19.7	$ 19.2
Changes in liability for future policyholder benefits	$ 6	$ 1.9

Basis of Presentation and Accou

Basis of Presentation and Accounting Policies	3 Months Ended
Basis of Presentation and Accounting Policies	Mar. 31, 2024
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Presentation and Accounting Policies	Basis of Presentation and Accounting Policies The unaudited Condensed Consolidated Financial Statements include the accounts of Kemper Corporation (“Kemper”) and its subsidiaries which include property and casualty insurance subsidiaries, life insurance subsidiaries (collectively referred to herein as the “Company”), and a variable interest entity (“VIE”) in which the Company is considered the primary beneficiary. The unaudited Condensed Consolidated Financial Statements included herein have been prepared in accordance with generally accepted accounting principles in the United States of America (“GAAP”) on a basis consistent with reporting interim financial information pursuant to the rules and regulations for Form 10-Q and Article 10 of Regulation S-X of the Securities and Exchange Commission (“SEC”) and include the accounts of Kemper Corporation and its subsidiaries, and a VIE in which the Company is considered the primary beneficiary. All intercompany accounts and transactions have been eliminated. Certain financial information that is included in the annual financial statements, including certain financial statement footnote disclosures, prepared in accordance with GAAP is not required by the rules and regulations of the SEC for interim financial reporting and has been condensed or omitted. In the opinion of the Company’s management, the Condensed Consolidated Financial Statements include all adjustments necessary to fairly present the financial position, results of operations and cash flows for the periods presented. The preparation of financial statements requires significant management estimates. Due to this factor and other factors, such as the seasonal nature of some portions of the insurance business, annualizing the results of operations for the three months ended March 31, 2024 would not necessarily be indicative of the results expected for the full fiscal year. The accompanying Condensed Consolidated Financial Statements should be read in conjunction with the Company’s Consolidated Financial Statements and related notes included in Kemper’s Annual Report for the year ended December 31, 2023. Adoption of New Accounting Guidance The Company has adopted all recently issued accounting pronouncements with effective dates prior to March 31, 2024. Guidance Adopted in 2024 In March 2023, the FASB issued ASU 2023-02 Accounting for Investments in Tax Credit Structures Using the Proportional Amortization Method , which expands the use of the proportional amortization method of accounting to equity investments in other tax credit structures that meet certain criteria. The proportional amortization method results in the tax credit investment being amortized in proportion to the allocation of tax credits and other tax benefits in each period, and a net presentation within the income tax line item. ASU 2023-02 is effective for annual periods beginning after December 15, 2023 and interim periods within those annual periods. The Company adopted the new standard on January 1, 2024. The adoption did not have a material impact on the Company's Condensed Consolidated Financial Statements. Guidance Not Yet Adopted In October 2023, the FASB issued ASU 2023-06 Disclosure Improvements: Codification Amendments in Response to the SEC’s Disclosure Update and Simplification Initiative. This ASU amends the disclosure or presentation requirements related to various subtopics in the FASB Accounting Standards Codification. For SEC registrants, the effective date for each amendment will be the date on which the SEC’s removal of that related disclosure requirement from Regulation S-X or Regulation S-K becomes effective, with early adoption prohibited. The Company will monitor the removal of various requirements from the current regulations in order to determine when to adopt the related amendments, but does not anticipate the adoption of the new guidance will have a material impact on the Company’s Condensed Consolidated Financial Statements. The Company will continue to evaluate the impact of this guidance on its consolidated financial statements. In November 2023, the FASB issued ASU 2023-07 Improvements to Reportable Segment Disclosures , which enhances disclosures about significant segment expenses. The new standard does not change the definition or aggregation of operating segments but will add required disclosures of significant expenses for each reportable segment as well as certain other disclosures to help financial statement users understand how the chief operating decision maker evaluates segment expenses and operating results. ASU 2023-07 is effective for annual periods beginning after December 15, 2023 and interim periods within fiscal years beginning after December 15, 2024. The Company is currently evaluating the impact of this guidance on its consolidated financial statements. Note 1 - Basis of Presentation and Accounting Policies (Continued) In December 2023, the FASB issued ASU 2023-09 Improvements to Income Tax Disclosures , which improves the transparency of income tax disclosures by requiring companies to use consistent categories and greater disaggregation of information in the tax rate reconciliation as well as requiring disaggregation of income taxes paid by jurisdiction. ASU 2023-09 is effective for annual periods beginning after December 15, 2024, with early adoption permitted for annual financial statements that have not yet been issued or made available for issuance. The Company is currently evaluating the impact of this guidance on its consolidated financial statements. In March 2024, the SEC adopted a final rule requiring registrants to disclose certain climate-related information in their registration statements and annual reports. The rule requires the disclosure of qualitative and quantitative information, with certain information, such as financial statement effects of severe weather events, included in the notes to the audited financial statements. Other disclosure requirements include material climate-related risks, processes to manage and govern those risks, disclosure of targets if the targets materially affect or are reasonably likely to materially affect the Company, and, if material, disclosure of certain greenhouse gas emissions. On April 4, 2024, the SEC issued a voluntary stay of the final rule, pending the outcome of pending litigation. The requirements will be applied prospectively and have phased-in effective dates. For the Company, the Form 10-K for the year ended December 31, 2025, will be the first annual report with new climate-related disclosures. The Company is currently evaluating the impact of adopting the final rule.

Net Income (Loss) Per Unrestric

Net Income (Loss) Per Unrestricted Share	3 Months Ended
Net Income (Loss) Per Unrestricted Share	Mar. 31, 2024
Earnings Per Share [Abstract]
Net Income (Loss) Per Unrestricted Share	Net Income (Loss) Per Unrestricted Share A reconciliation of the numerator and denominator used in the calculation of Basic Net Income (Loss) Per Unrestricted Share and Diluted Net Income (Loss) Per Unrestricted Share for the three months ended March 31, 2024 and 2023 is presented below. Three Months Ended (Dollars in Millions, except per share amounts) Mar 31, Mar 31, Net Income (Loss) attributable to Kemper Corporation $ 71.3 $ (80.1) Shares in Thousands Weighted-average Unrestricted Shares Outstanding 64,254.5 63,946.6 Equity-based Compensation Equivalent Shares 518.3 — Weighted-average Unrestricted Shares and Equivalent Shares Outstanding Assuming Dilution 64,772.8 63,946.6 Net Income (Loss) attributable to Kemper Corporation per Unrestricted Share: (Per Unrestricted Share in Whole Dollars) Basic Net Income (Loss) Per Unrestricted Share $ 1.11 $ (1.25) Diluted Net Income (Loss) Per Unrestricted Share $ 1.10 $ (1.25) The number of shares of Kemper common stock that were excluded from the calculations of Equity-based Compensation Equivalent Shares and Weighted-average Unrestricted Shares and Equivalent Shares Outstanding Assuming Dilution because the effect of inclusion would be anti-dilutive was 1.7 million and 2.5 million for the three months ended March 31, 2024 and 2023, respectively.

Business Segments

Business Segments	3 Months Ended
Business Segments	Mar. 31, 2024
Segment Reporting [Abstract]
Business Segments	Business Segments The Company is engaged, through its subsidiaries, in the property and casualty insurance and life and health insurance businesses. The Company conducts its operations through two operating segments: Specialty Property & Casualty Insurance, and Life Insurance. The Specialty Property & Casualty Insurance segment’s principal products are specialty automobile and commercial automobile insurance. These products are distributed primarily through independent agents and brokers. The Life Insurance segment’s principal products are individual life, accident, supplemental health and property insurance. Career agents employed by the Company distribute these products. Corporate and Other operations include interest expense, board of directors fees, and Note 3 - Business Segments (Continued) general corporate expenses incurred by the Company which are not allocated to other businesses. Non-Core Operations includes the results of our Preferred Insurance business which we expect to fully exit. Segment Adjusted Operating Income (Loss) The Company analyzes the operating performance of each segment using segment adjusted operating income (loss) . Segment adjusted operating income (loss) does not equate to “ income (loss) before income taxes ” or “net income (loss)” as determined in accordance with U.S. GAAP but is the measure of segment profit or loss used by the Company’s Chief Operating Decision Maker (“CODM”) to evaluate segment performance and allocate resources, and consistent with authoritative guidance, is the measure of segment performance presented below. Segment adjusted operating income (loss) is calculated by adjusting each segment’s income (loss) before income taxes for the following items: (i) Change in Fair Value of Equity and Convertible Securities ; (ii) Net Realized Investment Gains ; (iii) Impairment Losses ; (iv) Acquisition and Disposition Related Transaction, Integration, Restructuring and Other Costs; (v) Debt Extinguishment, Pension Settlement and Other Charges; (vi) Goodwill Impairment Charge; (vii) Non-Core Operations; and (viii) Significant non-recurring or infrequent items that may not be indicative of ongoing operations These items are important to an understanding of overall results of operations. Segment adjusted operating income (loss) is not a substitute for income determined in accordance with U.S. GAAP, and the Company’s definition of segment adjusted operating income (loss) may differ from that used by other companies. The Company, however, believes that the presentation of segment adjusted consolidated operating income (loss) as measured for management purposes enhances the understanding of results of operations by highlighting the results from ongoing operations and the underlying profitability factors of its businesses. Earned Premiums by product line, including a reconciliation to Total Earned Premiums, for the three months ended March 31, 2024 and 2023 were: Three Months Ended (Dollars in Millions) Mar 31, Mar 31, Specialty Property & Casualty Insurance: Personal Automobile $ 675.3 $ 787.9 Commercial Automobile 164.7 156.3 Life Insurance: Life 80.6 82.2 Accident and Health 5.6 5.9 Property 11.1 11.2 Total Segment Earned Premiums 937.3 1,043.5 Non-Core Operations 94.6 137.4 Total Earned Premiums $ 1,031.9 $ 1,180.9 Note 3 - Business Segments (Continued) Segment Revenues, including a reconciliation to Total Revenues, for the three months ended March 31, 2024 and 2023 were: Three Months Ended (Dollars in Millions) Mar 31, Mar 31, Segment Revenues: Specialty Property & Casualty Insurance: Earned Premiums $ 840.0 $ 944.2 Net Investment Income 41.1 38.5 Change in Value of Alternative Energy Partnership Investments 0.3 0.4 Other Income 1.1 0.9 Total Specialty Property & Casualty Insurance 882.5 984.0 Life Insurance: Earned Premiums 97.3 99.3 Net Investment Income 44.3 49.8 Change in Value of Alternative Energy Partnership Investments 0.1 0.2 Other Income (Loss) 0.2 (0.4) Total Life Insurance 141.9 148.9 Total Segment Revenues 1,024.4 1,132.9 Change in Fair Value of Equity and Convertible Securities 3.4 1.7 Net Realized Investment Gains 6.6 6.4 Net Impairment Losses Recognized in Earnings (1.5) 2.1 Non-Core Operations 106.2 148.0 Other 3.9 3.7 Total Revenues $ 1,143.0 $ 1,294.8 Note 3 - Business Segments (Continued) Adjusted Consolidated Operating Income (Loss), including a reconciliation to Income (Loss) before Income Taxes attributable to Kemper Corporation, for the three months ended March 31, 2024 and 2023 was: Three Months Ended (Dollars in Millions) Mar 31, Mar 31, Segment Adjusted Operating Income (Loss): Specialty Property & Casualty Insurance $ 86.5 $ (74.7) Life Insurance 14.0 14.8 Total Segment Adjusted Operating Income (Loss) 100.5 (59.9) Corporate and Other Adjusted Operating Loss (15.6) (12.9) Less: (Loss) Income before Income Taxes attributable to Noncontrolling Interest (1.4) — Adjusted Consolidated Operating Income (Loss) 86.3 (72.8) Income (Loss) From: Change in Fair Value of Equity and Convertible Securities 3.4 1.7 Net Realized Investment Gains 6.6 6.4 Impairment Losses (1.5) 2.1 Acquisition and Disposition Related Transaction, Integration, Restructuring and Other Costs (12.8) (29.1) Non-Core Operations 6.0 (12.2) Income (Loss) before Income Taxes attributable to Kemper Corporation $ 88.0 $ (103.9) Adjusted Consolidated Net Operating Income (Loss), including a reconciliation to Net Income (Loss) attributable to Kemper Corporation, for the three months ended March 31, 2024 and 2023 was: Three Months Ended (Dollars in Millions and Net of Income Taxes) Mar 31, Mar 31, Segment Adjusted Net Operating Income (Loss): Specialty Property & Casualty Insurance $ 69.2 $ (58.4) Life Insurance 11.9 13.2 Total Segment Adjusted Net Operating Income (Loss) 81.1 (45.2) Corporate and Other Adjusted Net Operating Loss (12.5) (10.5) Less: Net (Loss) Income attributable to Noncontrolling Interest (1.1) — Adjusted Consolidated Net Operating Income (Loss) 69.7 (55.7) Net Income (Loss) From: Change in Fair Value of Equity and Convertible Securities 2.7 1.3 Net Realized Investment Gains 5.2 5.1 Impairment Losses (1.2) 1.7 Acquisition and Disposition Related Transaction, Integration, Restructuring and Other Costs (10.1) (23.0) Non-Core Operations 5.0 (9.5) Net Income (Loss) attributable to Kemper Corporation $ 71.3 $ (80.1)

Property and Casualty Insurance

Property and Casualty Insurance Reserves	3 Months Ended
Property and Casualty Insurance Reserves	Mar. 31, 2024
Liability for Future Policy Benefits and Unpaid Claims and Claims Adjustment Expense [Abstract]
Property and Casualty Insurance Reserves	Property and Casualty Insurance Reserves Property and Casualty Insurance Reserve activity for the three months ended March 31, 2024 and 2023 was: Three Months Ended (Dollars in Millions) Mar 31, Mar 31, Property and Casualty Insurance Reserves: Gross of Reinsurance at Beginning of Year $ 2,680.5 $ 2,756.9 Less Reinsurance Recoverables at Beginning of Year 27.8 39.6 Property and Casualty Insurance Reserves, Net of Reinsurance at Beginning of Year 2,652.7 2,717.3 Incurred Losses and LAE related to: Current Year 686.1 944.0 Prior Years 8.8 41.9 Total Incurred Losses and LAE 694.9 985.9 Paid Losses and LAE related to: Current Year 213.9 325.5 Prior Years 562.9 690.9 Total Paid Losses and LAE 776.8 1,016.4 Property and Casualty Insurance Reserves, Net of Reinsurance at End of Period 2,570.8 2,686.8 Plus Reinsurance Recoverables at End of Period 26.4 34.3 Property and Casualty Insurance Reserves, Gross of Reinsurance at End of Period $ 2,597.2 $ 2,721.1 Property and Casualty Insurance Reserves are estimated based on historical experience patterns and current economic trends. Actual loss experience and loss trends may differ from these historical experience patterns and economic conditions. Loss experience and loss trends emerge over several years from the dates of loss inception. The Company monitors such emerging loss trends on a quarterly basis. Changes in such estimates are included in the Condensed Consolidated Statements of Income (Loss) in the period of change. Additionally, the Company reviews if any premium revisions are appropriate as a result of any incurred losses and loss adjustment expenses (“LAE”) related to prior years recorded in the current period. For the three months ended March 31, 2024 and 2023, no additional premiums or return premiums were recorded. For the three months ended March 31, 2024, the Company increased its Property and Casualty Insurance Reserves by $8.8 million to recognize adverse development of loss and LAE reserves from prior accident years. Specialty Personal Automobile insurance loss and LAE reserves developed adversely by $7.1 million due primarily to higher than expected settlements for extra-contractual demands related to prior year claims. Commercial Automobile insurance loss and LAE reserves developed favorably by $1.1 million due to favorable emergence in loss patterns related to policy years 2022 and 2023 bodily injury coverages. Non-Core personal automobile insurance loss and LAE reserves developed favorably by $2.9 million. Homeowners insurance loss and LAE reserves developed adversely by $3.6 million due to higher than expected losses associated with third quarter of 2023 catastrophe events and a higher than expected large loss emergence. Other personal lines loss and LAE reserves developed adversely by $2.2 million. For the three months ended March 31, 2023, the Company increased its Property and Casualty Insurance Reserves by $41.9 million to recognize adverse development of loss and LAE reserves from prior accident years. Specialty Personal Automobile insurance loss and LAE reserves developed adversely by $22.9 million due primarily to higher than expected emergence in loss patterns related to third and fourth accident quarters of 2022 within the bodily injury and physical damage coverages. Commercial Automobile insurance loss and LAE reserves developed adversely by $8.2 million due to higher than expected emergence in loss patterns related to 2021 and 2022 bodily injury coverages. Non-Core personal automobile insurance loss and LAE reserves developed adversely by $3.4 million due to higher than expected emergence in loss patterns related to the third and fourth accident quarters of 2022 within the physical damage coverages. Homeowners insurance loss and LAE reserves developed adversely by $5.5 million. Other personal lines loss and LAE reserves developed adversely by $1.9 million due to higher than expected loss patterns related to fourth quarter 2022 non-weather and weather related losses. Note 4 - Property and Casualty Insurance Reserves (Continued) The Company cannot predict whether loss and LAE reserves will develop favorably or unfavorably from the amounts reported in the Condensed Consolidated Financial Statements. The Company believes that any such development will not have a material effect on the Company’s Condensed Consolidated Shareholders’ Equity, but could have a material effect on the Company’s consolidated financial results for a given period. The Company’s Life Insurance Reserves are reported using the Company’s estimate of its liability for future policyholder benefits. The liability for future policyholder benefits is grouped by contract type and issue year into cohorts consistent with the grouping used in estimating the associated liability. Significant assumption inputs to the calculation of the liability for future policyholder benefits include mortality, lapses, and discount rates (both accretion and current). The Company’s actuaries review assumptions used to measure the liability for future policyholder benefits for nonparticipating traditional and limited pay long-duration contracts at least annually. If there is a change, assumptions are updated with the recognition and remeasurement recorded in the Company’s Condensed Consolidated Statements of Income (Loss). The Company’s actuaries use a variety of generally accepted actuarial methodologies, in accordance with Actuarial Standards of Practice, in determining the assumptions. A key assumption in these estimation methodologies is that patterns observed in prior periods are indicative of how policyholder benefits are expected to develop in the future and that such historical data can be used to predict and estimate future losses. However, changes in the Company’s business processes and the macroeconomic environment, by their very nature, are likely to affect the actual to expected experience which generally results in the historical experience factors becoming less reliable over time in predicting how cash flows will ultimately develop. The Company’s actuaries use professional judgment in determining how much weight to place on the actual to expected experience based on the older historical data and how much weight to place on more recent experience data. In some cases, the Company’s actuaries make adjustments to the assumptions to estimate losses. These assumptions are reviewed by the Company’s actuaries and corporate management who apply their collective judgment and determine the appropriate assumptions to adopt for the underlying business. Numerous factors are considered in this determination process, including, but not limited to, the assessed reliability of key assumptions that may be significantly influencing the current actuarial indications, changes in pricing and product offerings, changes in customer base, changes in agency operations or other changes that affect the timing of payments, the policyholder behaviors observed over the recent past, the level of volatility within a particular line of business, and the improvement or deterioration of actuarial indications in the current period as compared to prior periods. Changes in the Company’s assumptions underlying these liabilities over time will occur and may be material. Note 5 - Liability for Future Policyholder Benefits (Continued) The following tables summarize balances and changes in the present value of expected net premiums, present value of expected future policyholder benefits and net liability for future policyholder benefits as of and for the three months ended March 31, 2024 and 2023: Three Months Ended (Dollars in Millions) Mar 31, 2024 Mar 31, 2023 Present Value of Expected Net Premiums Balance, Beginning of Year $ 675.4 $ 688.6 Beginning Balance at Original Discount Rate $ 694.7 $ 728.9 Effect of Changes in Cash Flow Assumptions — — Effect of Actual Variances from Expected Experience 5.3 0.7 Adjusted Beginning of Year Balance 700.0 729.6 Issuances 38.2 31.8 Interest Accrual 7.6 7.0 Net Premiums Collected (22.7) (23.9) Ending Balance at Original Discount Rate 723.1 744.5 Effect of Changes in Discount Rate Assumptions (33.0) (22.1) Balance, End of Period $ 690.1 $ 722.4 Present Value of Expected Future Policyholder Benefits Balance, Beginning of Year $ 3,613.2 $ 3,561.0 Beginning Balance at Original Discount Rate $ 3,835.9 $ 3,906.2 Effect of Changes in Cash Flow Assumptions — — Effect of Actual Variances From Expected Experience 5.5 0.3 Adjusted Beginning of Year Balance 3,841.4 3,906.5 Issuances 38.2 31.8 Interest Accrual 42.6 42.4 Benefit Payments (56.5) (63.8) Ending Balance at Original Discount Rate 3,865.7 3,916.9 Effect of Changes in Discount Rate Assumptions (377.5) (217.4) Balance, End of Period $ 3,488.2 $ 3,699.5 Net Liability for Future Policyholder Benefits $ 2,798.1 $ 2,977.1 Less: Reinsurance Recoverable — — Net Liability for Future Policyholder Benefits, After Reinsurance Recoverable $ 2,798.1 $ 2,977.1 The weighted-average liability duration of the liability for future policyholder benefits as calculated under current rates is as follows: Mar 31, 2024 Mar 31, 2023 Weighted-Average Liability Duration of the Liability for Future Policyholder Benefits (Years) 14.6 14.9 The reconciliation of the net liability for future policyholder benefits to Life and Health Insurance Reserves in the Condensed Consolidated Balance Sheets is as follows: (Dollars in Millions) Mar 31, 2024 Mar 31, 2023 Net Liability for Future Policyholder Benefits $ 2,798.1 $ 2,977.1 Deferred Profit Liability 357.5 272.6 Other 1 138.7 149.9 Total Life and Health Insurance Reserves $ 3,294.3 $ 3,399.6 1 Other primarily consists of Accident and Health and Universal Life reserves Note 5 - Liability for Future Policyholder Benefits (Continued) The amounts of expected undiscounted future benefit payments, expected undiscounted future gross premiums and expected discounted future gross premiums, is as follows: (Dollars in Millions) Mar 31, 2024 Mar 31, 2023 Expected Future Benefit Payments, undiscounted $ 10,225.9 $ 10,177.7 Expected Future Gross Premiums, undiscounted $ 4,136.0 $ 4,464.2 Expected Future Gross Premiums, discounted $ 2,758.3 $ 2,931.1 The amount of revenue and interest recognized in the Condensed Consolidated Statements of Income (Loss) is as follows: Three Months Ended (Dollars in Millions) Mar 31, 2024 Mar 31, 2023 Gross Premiums or Assessments $ 101.3 $ 103.8 Interest Expense $ 35.0 $ 35.4 The weighted-average interest rate is as follows: Mar 31, 2024 Mar 31, 2023 Interest Accretion Rate 4.55 % 4.55 % Current Discount Rate 5.40 % 5.05 % Significant assumption inputs to the calculation of the liability for future policyholder benefits include mortality, lapses, and discount rates (both accretion and current). The Company did not make any changes to mortality and lapse assumptions during the three months ended March 31, 2024 and 2023. Market data that underlies current discount rates was updated from December 31, 2023. The balances of and changes in Deferred Profit Liability as of and for the periods indicated are as follows: Three Months Ended (Dollars in Millions) Mar 31, 2024 Mar 31, 2023 Balance, Beginning of Year $ 337.8 $ 253.6 Profits Deferred 41.8 43.0 Interest Accrual 4.0 3.0 Amortization (25.9) (27.0) Effect of Actual Variances from Expected Experience and Other Changes (0.2) — Balance, End of Period $ 357.5 $ 272.6

Liability for Future Policyhold

Liability for Future Policyholder Benefits	3 Months Ended
Liability for Future Policyholder Benefits	Mar. 31, 2024
Insurance [Abstract]
Liability for Future Policyholder Benefits	Property and Casualty Insurance Reserves Property and Casualty Insurance Reserve activity for the three months ended March 31, 2024 and 2023 was: Three Months Ended (Dollars in Millions) Mar 31, Mar 31, Property and Casualty Insurance Reserves: Gross of Reinsurance at Beginning of Year $ 2,680.5 $ 2,756.9 Less Reinsurance Recoverables at Beginning of Year 27.8 39.6 Property and Casualty Insurance Reserves, Net of Reinsurance at Beginning of Year 2,652.7 2,717.3 Incurred Losses and LAE related to: Current Year 686.1 944.0 Prior Years 8.8 41.9 Total Incurred Losses and LAE 694.9 985.9 Paid Losses and LAE related to: Current Year 213.9 325.5 Prior Years 562.9 690.9 Total Paid Losses and LAE 776.8 1,016.4 Property and Casualty Insurance Reserves, Net of Reinsurance at End of Period 2,570.8 2,686.8 Plus Reinsurance Recoverables at End of Period 26.4 34.3 Property and Casualty Insurance Reserves, Gross of Reinsurance at End of Period $ 2,597.2 $ 2,721.1 Property and Casualty Insurance Reserves are estimated based on historical experience patterns and current economic trends. Actual loss experience and loss trends may differ from these historical experience patterns and economic conditions. Loss experience and loss trends emerge over several years from the dates of loss inception. The Company monitors such emerging loss trends on a quarterly basis. Changes in such estimates are included in the Condensed Consolidated Statements of Income (Loss) in the period of change. Additionally, the Company reviews if any premium revisions are appropriate as a result of any incurred losses and loss adjustment expenses (“LAE”) related to prior years recorded in the current period. For the three months ended March 31, 2024 and 2023, no additional premiums or return premiums were recorded. For the three months ended March 31, 2024, the Company increased its Property and Casualty Insurance Reserves by $8.8 million to recognize adverse development of loss and LAE reserves from prior accident years. Specialty Personal Automobile insurance loss and LAE reserves developed adversely by $7.1 million due primarily to higher than expected settlements for extra-contractual demands related to prior year claims. Commercial Automobile insurance loss and LAE reserves developed favorably by $1.1 million due to favorable emergence in loss patterns related to policy years 2022 and 2023 bodily injury coverages. Non-Core personal automobile insurance loss and LAE reserves developed favorably by $2.9 million. Homeowners insurance loss and LAE reserves developed adversely by $3.6 million due to higher than expected losses associated with third quarter of 2023 catastrophe events and a higher than expected large loss emergence. Other personal lines loss and LAE reserves developed adversely by $2.2 million. For the three months ended March 31, 2023, the Company increased its Property and Casualty Insurance Reserves by $41.9 million to recognize adverse development of loss and LAE reserves from prior accident years. Specialty Personal Automobile insurance loss and LAE reserves developed adversely by $22.9 million due primarily to higher than expected emergence in loss patterns related to third and fourth accident quarters of 2022 within the bodily injury and physical damage coverages. Commercial Automobile insurance loss and LAE reserves developed adversely by $8.2 million due to higher than expected emergence in loss patterns related to 2021 and 2022 bodily injury coverages. Non-Core personal automobile insurance loss and LAE reserves developed adversely by $3.4 million due to higher than expected emergence in loss patterns related to the third and fourth accident quarters of 2022 within the physical damage coverages. Homeowners insurance loss and LAE reserves developed adversely by $5.5 million. Other personal lines loss and LAE reserves developed adversely by $1.9 million due to higher than expected loss patterns related to fourth quarter 2022 non-weather and weather related losses. Note 4 - Property and Casualty Insurance Reserves (Continued) The Company cannot predict whether loss and LAE reserves will develop favorably or unfavorably from the amounts reported in the Condensed Consolidated Financial Statements. The Company believes that any such development will not have a material effect on the Company’s Condensed Consolidated Shareholders’ Equity, but could have a material effect on the Company’s consolidated financial results for a given period. The Company’s Life Insurance Reserves are reported using the Company’s estimate of its liability for future policyholder benefits. The liability for future policyholder benefits is grouped by contract type and issue year into cohorts consistent with the grouping used in estimating the associated liability. Significant assumption inputs to the calculation of the liability for future policyholder benefits include mortality, lapses, and discount rates (both accretion and current). The Company’s actuaries review assumptions used to measure the liability for future policyholder benefits for nonparticipating traditional and limited pay long-duration contracts at least annually. If there is a change, assumptions are updated with the recognition and remeasurement recorded in the Company’s Condensed Consolidated Statements of Income (Loss). The Company’s actuaries use a variety of generally accepted actuarial methodologies, in accordance with Actuarial Standards of Practice, in determining the assumptions. A key assumption in these estimation methodologies is that patterns observed in prior periods are indicative of how policyholder benefits are expected to develop in the future and that such historical data can be used to predict and estimate future losses. However, changes in the Company’s business processes and the macroeconomic environment, by their very nature, are likely to affect the actual to expected experience which generally results in the historical experience factors becoming less reliable over time in predicting how cash flows will ultimately develop. The Company’s actuaries use professional judgment in determining how much weight to place on the actual to expected experience based on the older historical data and how much weight to place on more recent experience data. In some cases, the Company’s actuaries make adjustments to the assumptions to estimate losses. These assumptions are reviewed by the Company’s actuaries and corporate management who apply their collective judgment and determine the appropriate assumptions to adopt for the underlying business. Numerous factors are considered in this determination process, including, but not limited to, the assessed reliability of key assumptions that may be significantly influencing the current actuarial indications, changes in pricing and product offerings, changes in customer base, changes in agency operations or other changes that affect the timing of payments, the policyholder behaviors observed over the recent past, the level of volatility within a particular line of business, and the improvement or deterioration of actuarial indications in the current period as compared to prior periods. Changes in the Company’s assumptions underlying these liabilities over time will occur and may be material. Note 5 - Liability for Future Policyholder Benefits (Continued) The following tables summarize balances and changes in the present value of expected net premiums, present value of expected future policyholder benefits and net liability for future policyholder benefits as of and for the three months ended March 31, 2024 and 2023: Three Months Ended (Dollars in Millions) Mar 31, 2024 Mar 31, 2023 Present Value of Expected Net Premiums Balance, Beginning of Year $ 675.4 $ 688.6 Beginning Balance at Original Discount Rate $ 694.7 $ 728.9 Effect of Changes in Cash Flow Assumptions — — Effect of Actual Variances from Expected Experience 5.3 0.7 Adjusted Beginning of Year Balance 700.0 729.6 Issuances 38.2 31.8 Interest Accrual 7.6 7.0 Net Premiums Collected (22.7) (23.9) Ending Balance at Original Discount Rate 723.1 744.5 Effect of Changes in Discount Rate Assumptions (33.0) (22.1) Balance, End of Period $ 690.1 $ 722.4 Present Value of Expected Future Policyholder Benefits Balance, Beginning of Year $ 3,613.2 $ 3,561.0 Beginning Balance at Original Discount Rate $ 3,835.9 $ 3,906.2 Effect of Changes in Cash Flow Assumptions — — Effect of Actual Variances From Expected Experience 5.5 0.3 Adjusted Beginning of Year Balance 3,841.4 3,906.5 Issuances 38.2 31.8 Interest Accrual 42.6 42.4 Benefit Payments (56.5) (63.8) Ending Balance at Original Discount Rate 3,865.7 3,916.9 Effect of Changes in Discount Rate Assumptions (377.5) (217.4) Balance, End of Period $ 3,488.2 $ 3,699.5 Net Liability for Future Policyholder Benefits $ 2,798.1 $ 2,977.1 Less: Reinsurance Recoverable — — Net Liability for Future Policyholder Benefits, After Reinsurance Recoverable $ 2,798.1 $ 2,977.1 The weighted-average liability duration of the liability for future policyholder benefits as calculated under current rates is as follows: Mar 31, 2024 Mar 31, 2023 Weighted-Average Liability Duration of the Liability for Future Policyholder Benefits (Years) 14.6 14.9 The reconciliation of the net liability for future policyholder benefits to Life and Health Insurance Reserves in the Condensed Consolidated Balance Sheets is as follows: (Dollars in Millions) Mar 31, 2024 Mar 31, 2023 Net Liability for Future Policyholder Benefits $ 2,798.1 $ 2,977.1 Deferred Profit Liability 357.5 272.6 Other 1 138.7 149.9 Total Life and Health Insurance Reserves $ 3,294.3 $ 3,399.6 1 Other primarily consists of Accident and Health and Universal Life reserves Note 5 - Liability for Future Policyholder Benefits (Continued) The amounts of expected undiscounted future benefit payments, expected undiscounted future gross premiums and expected discounted future gross premiums, is as follows: (Dollars in Millions) Mar 31, 2024 Mar 31, 2023 Expected Future Benefit Payments, undiscounted $ 10,225.9 $ 10,177.7 Expected Future Gross Premiums, undiscounted $ 4,136.0 $ 4,464.2 Expected Future Gross Premiums, discounted $ 2,758.3 $ 2,931.1 The amount of revenue and interest recognized in the Condensed Consolidated Statements of Income (Loss) is as follows: Three Months Ended (Dollars in Millions) Mar 31, 2024 Mar 31, 2023 Gross Premiums or Assessments $ 101.3 $ 103.8 Interest Expense $ 35.0 $ 35.4 The weighted-average interest rate is as follows: Mar 31, 2024 Mar 31, 2023 Interest Accretion Rate 4.55 % 4.55 % Current Discount Rate 5.40 % 5.05 % Significant assumption inputs to the calculation of the liability for future policyholder benefits include mortality, lapses, and discount rates (both accretion and current). The Company did not make any changes to mortality and lapse assumptions during the three months ended March 31, 2024 and 2023. Market data that underlies current discount rates was updated from December 31, 2023. The balances of and changes in Deferred Profit Liability as of and for the periods indicated are as follows: Three Months Ended (Dollars in Millions) Mar 31, 2024 Mar 31, 2023 Balance, Beginning of Year $ 337.8 $ 253.6 Profits Deferred 41.8 43.0 Interest Accrual 4.0 3.0 Amortization (25.9) (27.0) Effect of Actual Variances from Expected Experience and Other Changes (0.2) — Balance, End of Period $ 357.5 $ 272.6

Investments

Investments	3 Months Ended
Investments	Mar. 31, 2024
Investments, Debt and Equity Securities [Abstract]
Investments	Note 6 - Investments Fixed Maturities The amortized cost and fair values of the Company’s Investments in Fixed Maturities at March 31, 2024 were: Amortized Gross Unrealized Allowance for Expected Credit Losses Fair Value (Dollars in Millions) Gains Losses U.S. Government and Government Agencies and Authorities $ 582.3 $ 1.0 $ (94.9) $ — $ 488.4 States and Political Subdivisions 1,552.3 9.9 (205.8) (0.5) 1,355.9 Foreign Governments 5.2 — (0.6) — 4.6 Corporate Securities: Bonds and Notes 4,077.8 13.0 (448.0) (7.2) 3,635.6 Redeemable Preferred Stocks 9.0 0.1 (1.1) — 8.0 Collateralized Loan Obligations 952.5 1.1 (15.4) — 938.2 Other Mortgage- and Asset-backed 383.0 0.2 (42.3) — 340.9 Investments in Fixed Maturities $ 7,562.1 $ 25.3 $ (808.1) $ (7.7) $ 6,771.6 The amortized cost and fair values of the Company’s Investments in Fixed Maturities at December 31, 2023 were: Amortized Gross Unrealized Allowance for Expected Credit Losses Fair Value (Dollars in Millions) Gains Losses U.S. Government and Government Agencies and Authorities $ 594.1 $ 1.9 $ (84.5) $ — $ 511.5 States and Political Subdivisions 1,575.9 16.3 (189.8) (0.5) 1,401.9 Foreign Governments 4.4 — (0.6) — 3.8 Corporate Securities: Bonds and Notes 4,046.8 35.5 (383.8) (7.7) 3,690.8 Redeemable Preferred Stocks 9.0 0.1 (0.8) — 8.3 Collateralized Loan Obligations 973.6 0.7 (24.5) — 949.8 Other Mortgage- and Asset-backed 362.0 0.1 (46.3) — 315.8 Investments in Fixed Maturities $ 7,565.8 $ 54.6 $ (730.3) $ (8.2) $ 6,881.9 Other Receivables included $6.0 million and $0.9 million of unsettled sales of Investments in Fixed Maturities at March 31, 2024 and December 31, 2023, respectively. There were $21.7 million of unsettled purchases of Investments in Fixed Maturities included in Accrued Expenses and Other Liabilities as of March 31, 2024. There were no unsettled purchases of Investments in Fixed Maturities included in Accrued Expenses and Other Liabilities as of December 31, 2023. Note 6 - Investments (Continued) The amortized cost and estimated fair values of the Company’s Investments in Fixed Maturities at March 31, 2024 by contractual maturity were: (Dollars in Millions) Amortized Cost Fair Value Due in One Year or Less $ 195.2 $ 190.8 Due after One Year to Five Years 896.7 867.5 Due after Five Years to Ten Years 1,062.2 924.1 Due after Ten Years 3,604.5 3,125.0 Mortgage- and Asset-backed Securities Not Due at a Single Maturity Date 1,803.5 1,664.2 Investments in Fixed Maturities $ 7,562.1 $ 6,771.6 The expected maturities of the Company’s Investments in Fixed Maturities may differ from the contractual maturities because issuers may have the right to call or prepay obligations with or without call or prepayment penalties. Investments in Mortgage- and Asset-backed Securities Not Due at a Single Maturity Date at March 31, 2024 consisted of securities issued by the Government National Mortgage Association with a fair value of $227.4 million, securities issued by the Federal National Mortgage Association with a fair value of $95.3 million, securities issued by the Federal Home Loan Mortgage Corporation with a fair value of $62.5 million and securities of other non-governmental issuers with a fair value of $1,279.1 million. An aging of unrealized losses on the Company’s Investments in Fixed Maturities at March 31, 2024 is presented below. Less Than 12 Months 12 Months or Longer Total (Dollars in Millions) Fair Unrealized Fair Unrealized Fair Unrealized Fixed Maturities: U.S. Government and Government Agencies and Authorities $ 46.5 $ (1.6) $ 393.0 $ (93.3) $ 439.5 $ (94.9) States and Political Subdivisions 165.0 (3.3) 962.0 (202.5) 1,127.0 (205.8) Foreign Governments 0.9 — 1.7 (0.6) 2.6 (0.6) Corporate Securities: Bonds and Notes 432.3 (11.5) 2,801.7 (436.5) 3,234.0 (448.0) Redeemable Preferred Stocks — — 7.6 (1.1) 7.6 (1.1) Collateralized Loan Obligations 231.6 (0.8) 246.7 (14.6) 478.3 (15.4) Other Mortgage- and Asset-backed 14.9 (0.1) 292.5 (42.2) 307.4 (42.3) Total Fixed Maturities $ 891.2 $ (17.3) $ 4,705.2 $ (790.8) $ 5,596.4 $ (808.1) Investment-grade fixed maturity investments comprised $788.7 million and below-investment-grade fixed maturity investments comprised $19.4 million of the unrealized losses on investments in fixed maturities at March 31, 2024. For below-investment-grade fixed maturity investments in an unrealized loss position, the unrealized loss amount, on average, was approximately 6.4% of the amortized cost basis of the investment. Note 6 - Investments (Continued) An aging of unrealized losses on the Company’s Investments in Fixed Maturities at December 31, 2023 is presented below. Less Than 12 Months 12 Months or Longer Total (Dollars in Millions) Fair Unrealized Fair Unrealized Fair Unrealized Fixed Maturities: U.S. Government and Government Agencies and Authorities $ 52.0 $ (0.8) $ 401.6 $ (83.7) $ 453.6 $ (84.5) States and Political Subdivisions 112.9 (2.3) 928.3 (187.5) 1,041.2 (189.8) Foreign Governments — — 1.9 (0.6) 1.9 (0.6) Corporate Securities: Bonds and Notes 198.4 (5.5) 2,813.0 (378.3) 3,011.4 (383.8) Redeemable Preferred Stocks — — 7.9 (0.8) 7.9 (0.8) Collateralized Loan Obligations 38.8 (0.4) 747.7 (24.1) 786.5 (24.5) Other Mortgage- and Asset-backed 15.7 (0.1) 287.3 (46.2) 303.0 (46.3) Total Fixed Maturities $ 417.8 $ (9.1) $ 5,187.7 $ (721.2) $ 5,605.5 $ (730.3) Investment-grade fixed maturity investments comprised $704.8 million and below-investment-grade fixed maturity investments comprised $25.5 million of the unrealized losses on investments in fixed maturities at December 31, 2023. For below-investment-grade fixed maturity investments in an unrealized loss position, the unrealized loss amount, on average, was approximately 8.8% of the amortized cost basis of the investment. Fixed Maturities - Expected Credit Losses The following table sets forth the change in allowance for credit losses on fixed maturities available-for-sale by major security type for three months ended March 31, 2024. Accrued interest excluded from the amortized cost of fixed income securities total $74.8 million and $77.0 million as of March 31, 2024 and December 31, 2023, respectively, and is reported within the Other Receivables line of the Condensed Consolidated Balance Sheets. The Company monitors accrued interest and writes off amounts when they are not expected to be received. States and Political Subdivisions Corporate Bonds and Notes Total (Dollars in Millions) Balance, Beginning of Year $ 0.5 $ 7.7 $ 8.2 Reductions Due to Sales — (0.2) (0.2) Net Decrease in Allowance on Securities for which Expected Credit Losses were Previously Recognized — (0.3) (0.3) Balance, End of Period $ 0.5 $ 7.2 $ 7.7 Note 6 - Investments (Continued) The following table sets forth the change in allowance for credit losses on fixed maturities available-for-sale by major security type for the three months ended March 31, 2023. States and Political Subdivisions Corporate Bonds and Notes Total (Dollars in Millions) Balance, Beginning of Year $ 0.7 $ 8.9 $ 9.6 Additions for Securities for which No Previous Expected Credit Losses were — 0.3 0.3 Reductions Due to Sales — (1.9) (1.9) Net Increase (Decrease) in Allowance on Securities for which Expected Credit Losses were Previously Recognized 0.1 (0.7) (0.6) Balance, End of Period $ 0.8 $ 6.6 $ 7.4 Equity Securities Investments in Equity Securities at Fair Value were $230.1 million and $225.8 million at March 31, 2024 and December 31, 2023, respectively. Net unrealized gains arising during the three months ended March 31, 2024 and 2023 and recognized in earnings, related to such investments still held as of March 31, 2024 and March 31, 2023, were $3.9 million and $4.4 million, respectively. There were no unsettled purchases of Investments in Equity Securities at Fair Value at March 31, 2024 or December 31, 2023. There were $0.1 million and $0.1 million in unsettled sales of Investments in Equity Securities at Fair Value at March 31, 2024 and December 31, 2023, respectively. Equity Method Limited Liability Investments Equity Method Limited Liability Investments include investments in limited liability investment companies and limited partnerships in which the Company’s interests are not deemed minor and are accounted for under the equity method of accounting. The Company’s investments in Equity Method Limited Liability Investments are generally of a passive nature in that the Company does not take an active role in the management of the investment entity. The Company’s maximum exposure to loss at March 31, 2024 is limited to the total carrying value of $215.2 million. In addition, the Company had outstanding commitments totaling approximately $84.5 million to fund Equity Method Limited Liability Investments at March 31, 2024. At March 31, 2024, 2.9% of Equity Method Limited Liability Investments were reported without a reporting lag. Of the total carrying value, 4.8% were reported with a one-month lag, and the remainder were reported with a greater than one-month but less than three-month lag. There were no unsettled purchases or sales of Equity Method Limited Liability Investments at March 31, 2024 or December 31, 2023. Unsettled purchases and sales of Equity Method Limited Liability Investments are carried within Accrued Expenses and Other Liabilities and Other Receivables, respectively, on the Condensed Consolidated Balance Sheets. Alternative Energy Partnership Investments Alternative Energy Partnership Investments include partnerships formed to invest in newly installed residential solar leases and power purchase agreements. As a result of this investment, the Company has the right to certain investment tax credits and tax depreciation benefits, and to a lesser extent, cash flows generated from the installed solar systems leased to individual consumers for a fixed period of time. The Hypothetical Liquidation Book Value (“HLBV”) equity method of accounting is used for the Company’s investments in Alternative Energy Partnership Investments. The Company’s maximum exposure to loss at March 31, 2024 is limited to the total carrying value of $17.2 million. The Company has no outstanding commitments to fund Alternative Energy Partnership Investments as of March 31, 2024. Alternative Energy Partnership Investments are reported on a three-month lag. Note 6 - Investments (Continued) Loans to Policyholders Loans to Policyholders represents funds loaned to policyholders up to the cash surrender value of the associated insurance policies and are carried at the unpaid principal balances due to the Company from the policyholders. Interest income on policy loans is recognized in Net Investment Income at the contract interest rate when earned. Policy loans are fully collateralized by the cash surrender value of the associated insurance policies. The carrying values of the Company’s Loans to Policyholders at Unpaid Principal investment at March 31, 2024 and December 31, 2023 were $280.5 million and $281.2 million, respectively. Other Investments The carrying values of the Company’s Other Investments at March 31, 2024 and December 31, 2023 were: (Dollars in Millions) Mar 31, Dec 31, Equity Securities at Modified Cost $ 24.7 $ 32.6 Real Estate at Depreciated Cost 93.9 94.7 Mortgage Loans 93.1 99.8 Other 1.9 14.8 Total Other Investments $ 213.6 $ 241.9 Investments in Equity Securities at Modified Cost were $24.7 million and $32.6 million at March 31, 2024 and December 31, 2023, respectively. The Company performs a qualitative impairment analysis on a quarterly basis consisting of various factors such as earnings performance, current market conditions, changes in credit ratings, changes in the regulatory environment and other factors. If the qualitative analysis identifies the presence of impairment indicators, the Company estimates the fair value of the investment. If the estimated fair value is below the carrying value, the Company records an impairment in the Condensed Consolidated Statements of Loss to reduce the carrying value to the estimated fair value. When the Company identifies observable transactions of the same or similar securities to those held by the Company, the Company increases or decreases the carrying value to the observable transaction price. The Company did not recognize any changes in carrying value due to observable transactions for the three months ended March 31, 2024 and 2023. The Company recognized an impairment of $0.4 million on Equity Securities at Modified Cost for three months ended March 31, 2024 as a result of the Company’s impairment analysis. The Company did not recognize any impairments on Equity Securities at Modified Cost for three months ended March 31, 2023. The Company recognized no cumulative increases or decreases in the carrying value due to observable transactions and $7.1 million of cumulative impairments on Equity Securities at Modified Cost held as of March 31, 2024. Note 6 - Investments (Continued) Net Investment Income Net Investment Income for the three months ended March 31, 2024 and 2023 was: Three Months Ended (Dollars in Millions) Mar 31, Mar 31, Investment Income: Interest on Fixed Income Securities 1,2 $ 79.8 $ 81.5 Dividends on Equity Securities Excluding Alternative Investments 2.8 1.0 Alternative Investments: Equity Method Limited Liability Investments (2.1) 1.1 Limited Liability Investments Included in Equity Securities 3.4 2.6 Total Alternative Investments 1.3 3.7 Short-term Investments 7.3 2.3 Loans to Policyholders 5.2 5.4 Real Estate 2.3 2.4 Company-Owned Life Insurance 7.1 8.8 Other 2.5 3.0 Total Investment Income 108.3 108.1 Investment Expenses: Real Estate 2.2 2.1 Other Investment Expenses 1,2 5.7 4.2 Total Investment Expenses 7.9 6.3 Net Investment Income $ 100.4 $ 101.8 1 In the first quarter of 2024, the Company changed its presentation of the details of investment performance to report interest expense incurred on Federal Home Loan Bank ("FHLB") borrowings as an offset to interest on fixed income securities since FHLB borrowings are used for spread lending purposes. The interest expense incurred on FHLB borrowings was previously reported within Other Investment Expenses. The prior period amounts presented above have been updated to reflect this change in presentation. 2 Reduced by interest expense incurred on FHLB borrowings used for spread lending purposes of $5.2 million and $4.7 million, for the three months ended March 31, 2024 and 2023, respectively. Gross gains and losses on sales of investments in fixed maturities and gains and losses associated with Ultra-Long Treasury Futures for the three months ended March 31, 2024 and 2023 were: Three Months Ended (Dollars in Millions) Mar 31, Mar 31, Fixed Maturities: Gains on Sales $ 12.8 $ 1.1 Losses on Sales (2.3) (3.3) (Losses) Gains on Hedging Activity (7.9) 8.4

Derivatives

Derivatives	3 Months Ended
Derivatives	Mar. 31, 2024
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivatives	Note 7 - Derivatives The Company’s earnings, cash flows, and financial position are subject to fluctuations due to changes in prevailing interest rates. The Company entered into derivative agreements with maturity dates throughout 2024. Derivative instruments are carried at fair value on the Condensed Consolidated Balance Sheets. Derivative instruments in a gain position are presented within Other Investments and those in a loss position are included in Accrued Expenses and Other Liabilities. Changes in the fair values of Note 7 - Derivatives (Continued) derivatives are recorded on the Condensed Consolidated Statements of Income (Loss) within Net Realized Investment Gains or Accumulated Other Comprehensive Loss along with the corresponding change in the designated hedge assets. Interest Rate Risk The Company’s debt securities valuations utilize the Treasury designated benchmark rate, exposing the Company to variability due to changes in interest rates. Ultra-Long Treasury Futures The Company enters into exchange-traded ultra-long Treasury futures (“Treasury Futures”) in order to manage exposure to upcoming changes in the benchmark (Treasury) interest rate of forecasted transactions. These derivatives expire quarterly. As of March 31, 2024, all Treasury Futures held by the Company qualified for hedge accounting as a cash flow hedge. There were treasury futures that expired during the three months ended March 31, 2024, that did not qualify for hedge accounting. These positions are shown in the Treasury Futures section below. Primary Risks Managed by Derivatives The following table presents the derivative instruments, primary underlying risk exposure, gross notional amount, and estimated fair value of the Company’s derivatives: March 31, 2024 December 31, 2023 (Dollars in Millions) Estimated Fair Value Estimated Fair Value Derivative Instrument Primary Underlying Risk Exposure Gross Notional Amount Assets Liabilities Gross Notional Amount Assets Liabilities Derivatives Designated as Hedging Instruments: Treasury Futures Interest Rate Risk $ 74.9 $ 1.2 $ — $ — $ — $ — Derivatives Not Designated or Not Qualifying as Hedging Instruments: Treasury Futures Interest Rate Risk $ — $ — $ — $ 149.7 $ 14.7 $ — Effects of Derivatives on the Statements of Income (Loss) and Comprehensive Income (Loss) Cash Flow Hedges The below table reflects the amounts of Gains (Losses) deferred into AOCI, net changes in amounts in AOCI associated with current hedging transactions, amounts subsequently reclassified into Net Income (Loss) through Net Realized Investment Gains (Losses) for derivatives qualifying as cash flow hedges for the three months ended March 31, 2024 and 2023. Three Months Ended (Dollars in Millions) Mar 31, Mar 31, Beginning of Year $ — $ (0.4) Gains (Losses) Deferred in AOCI 1.5 (0.4) Net Change in AOCI with Current Period Hedging Transactions (1.3) — Gains (Losses) Reclassified into Income — (0.5) Net Comprehensive Gains (Losses) from Cash Flow Hedges $ 0.2 $ (1.3)

Fair Value Measurements

Fair Value Measurements	3 Months Ended
Fair Value Measurements	Mar. 31, 2024
Fair Value Disclosures [Abstract]
Fair Value Measurements	Fair Value Measurements The Company classifies its Investments in Fixed Maturities as available-for-sale and reports these investments at fair value. The Company reports equity investments with readily determinable fair values as Equity Securities at Fair Value. Certain investments that are measured at fair value using the net asset value practical expedient are not required to be classified using the fair value hierarchy, but are presented in the following two tables to permit reconciliation of the fair value hierarchy to the amounts presented in the Condensed Consolidated Balance Sheets. The valuation of assets and liabilities measured at fair value in Company’s Condensed Consolidated Balance Sheets at March 31, 2024 is summarized below. The Company had no material liabilities that are measured and reported at fair value. Fair Value Measurements (Dollars in Millions) Quoted Prices Significant Other Significant Measured at Net Asset Value Total Fair Value Assets: Fixed Maturities: U.S. Government and Government Agencies and Authorities $ 85.4 $ 403.0 $ — $ — $ 488.4 States and Political Subdivisions — 1,354.5 1.4 — 1,355.9 Foreign Governments — 4.6 — — 4.6 Corporate Securities: Bonds and Notes — 3,455.1 180.5 — 3,635.6 Redeemable Preferred Stock — 5.8 2.2 — 8.0 Collateralized Loan Obligations — 938.2 — — 938.2 Other Mortgage and Asset-backed — 335.8 5.1 — 340.9 Total Investments in Fixed Maturities 85.4 6,497.0 189.2 — 6,771.6 Equity Securities at Fair Value: Preferred Stocks: Finance, Insurance and Real Estate — 15.9 — — 15.9 Other Industries — 7.8 2.2 — 10.0 Common Stocks: Finance, Insurance and Real Estate 0.6 — — — 0.6 Other Industries 0.3 — 0.5 — 0.8 Other Equity Interests: Exchange Traded Funds 8.7 — — — 8.7 Limited Liability Companies and Limited Partnerships — — — 194.1 194.1 Total Investments in Equity Securities at Fair Value 9.6 23.7 2.7 194.1 230.1 Other Investments: Derivative Instrument Classified as Cash Flow Hedge — 1.2 — — 1.2 Total Assets $ 95.0 $ 6,521.9 $ 191.9 $ 194.1 $ 7,002.9 Within the Condensed Consolidated Balance Sheets, the Company discloses the fair value of its Long-term Debt. This fair value is determined using broker/dealer quotes of similar securities, and as such, would be included in Level 2 of the fair value hierarchy. Note 8 - Fair Value Measurements (Continued) The valuation of assets and liabilities measured at fair value in the Company’s Consolidated Balance Sheets at December 31, 2023 is summarized below. The Company had no material liabilities that are measured and reported at fair value. Fair Value Measurements (Dollars in Millions) Quoted Prices Significant Other Significant Measured at Net Asset Value Total Fair Value Assets: Fixed Maturities: U.S. Government and Government Agencies and Authorities $ 98.8 $ 412.7 $ — $ — $ 511.5 States and Political Subdivisions — 1,401.8 0.1 — 1,401.9 Foreign Governments — 3.8 — — 3.8 Corporate Securities: Bonds and Notes — 3,513.7 177.1 — 3,690.8 Redeemable Preferred Stocks — 1.2 7.1 — 8.3 Collateralized Loan Obligations — 949.8 — — 949.8 Other Mortgage and Asset-backed — 310.6 5.2 — 315.8 Total Investments in Fixed Maturities 98.8 6,593.6 189.5 — 6,881.9 Equity Securities at Fair Value: Preferred Stocks: Finance, Insurance and Real Estate — 15.6 — — 15.6 Other Industries — 7.5 2.4 — 9.9 Common Stocks: Finance, Insurance and Real Estate 0.6 — — — 0.6 Other Industries 0.2 — 0.4 — 0.6 Other Equity Interests: Exchange Traded Funds 7.7 — — — 7.7 Limited Liability Companies and Limited Partnerships — — — 191.4 191.4 Total Investments in Equity Securities at Fair Value 8.5 23.1 2.8 191.4 225.8 Other Investments: Derivative Instruments Not Designated as Hedges — 14.7 — — 14.7 Total Assets $ 107.3 $ 6,631.4 $ 192.3 $ 191.4 $ 7,122.4 The Company’s investments in Fixed Maturities that are classified as Level 1 primarily consist of U.S. Treasury Bonds and Notes. The Company’s investments in Equity Securities at Fair Value that are classified as Level 1 consist of either investments in publicly-traded common stocks or exchange traded funds. The Company’s investments in Fixed Maturities that are classified as Level 2 primarily consist of investments in corporate bonds, obligations of states and political subdivisions, collateralized loan obligations, and mortgage-backed securities of U.S. government agencies. The Company’s investments in Equity Securities at Fair Value that are classified as Level 2 primarily consist of investments in preferred stocks. The Company’s Derivative Instruments Designated as Cash Flow Hedges that are classified as Level 2 primarily consist of hedges to manage exposure to upcoming changes in the benchmark (Treasury) interest rate of forecasted transactions. The Company uses a leading, nationally recognized provider of market data and analytics to price the vast majority of the Company’s Level 2 measurements. The provider utilizes evaluated pricing models that vary by asset class and incorporate available trade, bid and other market information. Because many fixed maturity securities do not trade on a daily basis, the provider’s evaluated pricing Note 8 - Fair Value Measurements (Continued) applications apply available information through processes such as benchmark curves, benchmarking of like securities, sector groupings and matrix pricing to prepare evaluations. In addition, the provider uses model processes to develop prepayment and interest rate scenarios. The pricing provider’s models and processes also take into account market convention. For each asset class, teams of its evaluators gather information from market sources and integrate relevant credit information, perceived market movements and sector news into the evaluated pricing applications and models. The Company generally validates the measurements obtained from its primary pricing provider by comparing them with measurements obtained from one additional pricing provider that provides either prices from recent market transactions, quotes in inactive markets or evaluations based on its own proprietary models. The Company investigates significant differences related to the values provided. On completion of its investigation, management exercises judgment to determine the price selected and whether adjustments, if any, to the price obtained from the Company’s primary pricing provider would warrant classification of the price as Level 3. In instances where a measurement cannot be obtained from either pricing provider, the Company generally will evaluate bid prices from one or more binding quotes obtained from market makers to value investments in inactive markets and classified by the Company as Level 2. The Company generally classifies securities when it receives non-binding quotes or indications as Level 3 securities unless the Company can validate the quote or indication against recent transactions in the market. The table below presents quantitative information about the significant unobservable inputs utilized by the Company in determining fair values for fixed maturity investments classified as Level 3 at March 31, 2024. Valuations for assets presented in the tables below are primarily based on broker/dealer quotes for which there is a lack of transparency as to inputs used to develop the valuations. The quantitative detail of these unobservable inputs is neither provided nor reasonably available to the Company. The weighted average yield is calculated based on fair value. (Dollars in Millions) Unobservable Input Total Fair Value Range of Unobservable Inputs Weighted-average Yield Investment-grade Market Yield $ 55.3 1.8 % - 13.5 % 7.9 % Non-investment-grade: Senior Debt Market Yield 31.7 7.0 - 48.0 13.0 Junior Debt Market Yield 35.8 11.0 - 25.5 13.2 Other Various 66.4 Total Level 3 Fixed Maturity Investments $ 189.2 The table below presents quantitative information about the significant unobservable inputs utilized by the Company in determining fair values for fixed maturity investments classified as Level 3 at December 31, 2023. Valuations for assets presented in the tables below are primarily based on broker/dealer quotes for which there is a lack of transparency as to inputs used to develop the valuations. The quantitative detail of these unobservable inputs is neither provided nor reasonably available to the Company. The weighted average yield is calculated based on fair value. (Dollars in Millions) Unobservable Input Total Fair Value Range of Unobservable Inputs Weighted-average Yield Investment-grade Market Yield $ 60.0 4.2 % - 15.8 % 8.7 % Non-investment-grade: Senior Debt Market Yield 32.6 9.2 - 36.7 13.5 Junior Debt Market Yield 32.5 11.8 - 22.5 13.8 Other Various 64.4 Total Level 3 Fixed Maturity Investments $ 189.5 Note 8 - Fair Value Measurements (Continued) For an investment in a fixed maturity security, an increase in the yield used to determine the fair value of the security will decrease the fair value of the security. A decrease in the yield used to determine fair value will increase the fair value of the security, but for callable securities the fair value increase is generally limited to par, unless security is currently callable at a premium. Information by security type pertaining to the changes in the fair value of the Company’s investments classified as Level 3 for the three months ended March 31, 2024 is presented below. Fixed Maturities Equity Securities (Dollars in Millions) Corporate States and Political Redeemable Other Mortgage- Preferred Total Balance, Beginning of Year $ 177.1 $ 0.1 $ 7.1 $ 5.2 $ 2.8 $ 192.3 Total (Losses) Gains: Included in Condensed Consolidated Statements of Income (Loss) (0.2) — — — (0.1) (0.3) Included in Other Comprehensive Income 2.3 (0.4) — (0.1) — 1.8 Purchases 13.2 — — — — 13.2 Sales (3.7) — — — — (3.7) Transfers into Level 3 — 1.7 — — — 1.7 Transfers out of Level 3 (8.2) — (4.9) — — (13.1) Balance, End of Period $ 180.5 $ 1.4 $ 2.2 $ 5.1 $ 2.7 $ 191.9 The transfers into and out of Level 3 were due primarily to changes in the availability of market observable inputs. Information by security type pertaining to the changes in the fair value of the Company’s investments classified as Level 3 for the three months ended March 31, 2023 is presented below. Fixed Maturities Equity Securities (Dollars in Millions) Corporate Redeemable Other Mortgage- Preferred Total Balance, Beginning of Year $ 216.0 $ 6.8 $ 5.1 $ 2.1 $ 230.0 Total Gains (Losses): Included in Condensed Consolidated Statements of Income (Loss) 0.4 — — (0.5) (0.1) Included in Other Comprehensive Income 1.5 — 0.2 — 1.7 Purchases 19.4 — — — 19.4 Sales (41.2) — — — (41.2) Transfers into Level 3 — — — 0.4 0.4 Balance, End of Period $ 196.1 $ 6.8 $ 5.3 $ 2.0 $ 210.2 The transfers into and out of Level 3 were due primarily to changes in the availability of market observable inputs. Note 8 - Fair Value Measurements (Continued) The table below shows investments reported at fair value using NAV and their unfunded commitments by asset class as of March 31, 2024 and December 31, 2023. (Dollars in Millions) March 31, 2024 December 31, 2023 Asset Class Fair Value Using NAV Unfunded Commitments Fair Value Using NAV Unfunded Commitments Reported as Equity Method Limited Liability Investments: Mezzanine Debt $ 123.2 $ 42.6 $ 125.4 $ 43.1 Real Estate 42.0 — 41.9 — Senior Debt 19.2 39.5 19.0 39.9 Leveraged Buyout 8.5 0.6 8.6 0.6 Secondary Transactions 6.8 1.6 7.9 1.7 Distressed Debt 6.1 — 7.9 — Growth Equity 0.8 — 1.2 — Hedge Fund 0.1 — 0.1 — Other 8.5 0.2 9.7 — Total Equity Method Limited Liability Investments 215.2 84.5 221.7 85.3 Reported as Other Equity Interests at Fair Value: Mezzanine Debt 127.7 66.3 124.0 67.0 Senior Debt 24.7 10.8 24.8 10.6 Leveraged Buyout 19.7 9.5 19.0 10.0 Distressed Debt 12.9 13.0 12.4 13.0 Growth Equity 6.3 6.5 6.4 6.5 Secondary Transactions 2.7 3.1 2.8 3.1 Hedge Funds — — 1.9 — Real Estate 0.1 0.2 0.1 0.2 Total Reported as Other Equity Interests at Fair Value 194.1 109.4 191.4 110.4 Reported as Equity Securities at Modified Cost: Other 4.6 — 4.8 — Total Reported as Equity Securities at Modified Cost 4.6 — 4.8 — Total Investments in Limited Liability Companies and Limited Partnerships $ 413.9 $ 193.9 $ 417.9 $ 195.7 The fund investments included above (excluding Hedge Funds) are not redeemable, because distributions from the funds will be received when underlying investments of the funds are liquidated. The funds are generally expected to have approximately 10 year lives at their inception, but these lives may be extended at the fund manager’s discretion, typically in one or two-year increments. The hedge fund investments included above, which are carried at fair value, are generally redeemable subject to the redemption notices period. The majority of the hedge fund investments are redeemable monthly or quarterly. Note 8 - Fair Value Measurements (Continued) The following table includes information related to the Company’s investments in certain private equity funds or hedge funds that calculate a net asset value per share: Asset Class Investment Category Includes Mezzanine Debt Funds with investments in junior or subordinated debt and potentially minority equity securities issued by private companies. Senior Debt Funds with investments in senior or first lien debt and potentially minority equity securities typically issued by private companies. Distressed Debt Funds with debt or minority equity investments that are made opportunistically in companies that are in or near default or under financial strain with potential to have an active role in restructuring company. Secondary Transactions Funds that focus on purchasing third party fund interests from investors seeking liquidity within their own portfolio. Hedge Fund Funds that focus primarily on investing in public securities with strategy of generating uncorrelated returns to the public markets. Leveraged Buyout Funds with control equity investments in more mature, positive cash flowing, private companies that are typically purchased with the use of financial leverage. Growth Equity Funds that invest in early or venture stage companies with high growth potential with view towards generating realizations through sale or initial public offering (“IPO”) of company. Real Estate Funds with investments in multi-family housing properties. Other Consists of direct investments of preferred equity or minority common equity investments into private companies structured as limited partnerships or limited liability companies. Presented below are the carrying values and fair value estimates of financial instruments not carried at fair value. March 31, 2024 December 31, 2023 (Dollars in Millions) Carrying Value Fair Value Carrying Value Fair Value Financial Assets: Loans to Policyholders $ 280.5 $ 280.5 $ 281.2 $ 281.2 Short-term Investments 520.7 520.7 520.9 520.9 Mortgage Loans 93.1 93.1 99.8 99.8 Company-Owned Life Insurance 515.7 515.7 513.5 513.5 Equity Securities at Modified Cost 24.7 24.7 32.6 32.6 Financial Liabilities: Long-term Debt $ 1,389.8 $ 1,246.8 $ 1,389.2 $ 1,213.4 Policyholder Obligations 563.2 563.2 557.4 557.4 Loans to policyholders are carried at unpaid principal balance which approximates fair value and are categorized as Level 3 within the fair value hierarchy. The nature of policy loans is to have a negligible default risk as the loans are fully collateralized by the value of the policy. Policy loans do not have a stated maturity and the balances and accrued interest are repaid either by the policyholder or with proceeds from the policy. Due to the collateralized nature of policy loans and unpredictable timing of payments, the Company believes the carrying value of policy loans approximates fair value. The fair value measurement of Short-term Investments is estimated using inputs that are considered either Level 1 or Level 2 measurements. The Mortgage Loans fair value measurement is considered equal to amortized cost given the short-term nature of the investments. The fair value measurement of Equity Securities at Modified Cost is estimated using inputs that are considered Level 3 measurements. The cash surrender value of Company-Owned Life Insurance approximates fair value and is considered to be a Level 2 investment. The fair value of Long-term Debt is estimated using quoted prices for similar liabilities in markets that are not active. The inputs used in the valuation are considered Level 2 measurements. Policyholder Obligations presented in the preceding table consist of advances from the FHLB of Chicago, and the inputs used in the valuation are considered Level 2 measurements.

Variable Interest Entities

Variable Interest Entities	3 Months Ended
Variable Interest Entities	Mar. 31, 2024
Equity Method Investments and Joint Ventures [Abstract]
Variable Interest Entity Disclosure	Variable Interest Entities A VIE is a legal entity that does not have sufficient equity at risk to finance its activities without additional subordinated financial support or is structured such that equity investors lack the ability to make significant decisions relating to the entity's operations through voting rights or do not substantively participate in the gains and losses of the entity. The Company consolidates VIEs in which the Company is deemed the primary beneficiary. The primary beneficiary is the entity that has both (1) the power to direct the activities of the VIE that most significantly affect that entity's economic performance and (2) the obligation to absorb losses or the right to receive benefits that could be potentially significant to the VIE. Reciprocal Exchange The Company has formed a management company that acts as attorney-in-fact (“AIF”) for Kemper Reciprocal (the “Reciprocal Exchange” or “Exchange”), an Illinois-domiciled reciprocal insurance exchange. The Exchange principally writes specialty personal automobile policies sold to subscribers of the Exchange. The establishment of Kemper Reciprocal was completed in the third quarter of 2023. The Company consolidates the Exchange since (1) the AIF manages the business operations of the Exchange and therefore has the power to direct the activities that most significantly impact the economic performance of the Exchange and (2) the Company has provided capital to the Exchange and would absorb any expected losses that could potentially be significant to the Exchange. The Exchange’s anticipated economic performance is the product of its underwriting and investment results. The AIF receives a management fee for the services provided to the Reciprocal Exchange. The management fee revenues are based upon all premiums written or assumed by the Exchange. The AIF determines the management fee rate to be paid by the Exchange. This rate cannot exceed 30% of the Exchange’s gross written and assumed premiums. The assets of the Reciprocal Exchange can be used only to settle the obligations of the Reciprocal Exchange for which creditors and other beneficial owners have no recourse to the Company. The Company has no obligation related to any underwriting and/or investment losses experienced by the Exchange. As of December 31, 2023, the Company had contributed $4.0 million of surplus to the Reciprocal Exchange. During the first quarter of 2024, the Company contributed an additional $2.0 million of surplus to the Reciprocal Exchange, resulting in a total contributed surplus of $6.0 million as of March 31, 2024. The effects of the transactions between the Company and the Reciprocal Exchange are eliminated in consolidation to derive consolidated Net Income (Loss). However, the management fee income earned by the AIF is reported in Net Income (Loss) attributable to Kemper Corporation and is included in the basic and diluted earnings per share. Noncontrolling interest is the portion of equity (net assets) not attributable, directly or indirectly, to a parent. Since the Company has no ownership interest in Kemper Reciprocal, the difference between the carrying value of the Exchange’s assets and liabilities represents noncontrolling interest and any income or loss generated by the net assets of the Exchange is presented as income or loss attributable to noncontrolling interest. Alternative Energy Partnership The Company invests in an Alternative Energy Partnership formed to provide sustainable energy projects that are designed to generate a return primarily through the realization of federal tax credits. This entity was formed to invest in newly installed residential solar leases and power purchase agreements. As a result of this investment, the Company has the right to certain investment tax credits and tax depreciation benefits, and to a lesser extent, cash flows generated from the installed solar systems leased to individual consumers. The Company’s interest in the Alternative Energy Partnership Investment is considered an investment in a VIE. The Company has determined that it is not the primary beneficiary as it does not have the power to direct the activities that most significantly impact the economic performance of the entity and therefore is not required to consolidate the VIE. The project sponsor governs the entity and the Company only has consent rights that have been deemed protective in nature and does not participate in key economic decisions of the entity. The investment is accounted for using the equity method of accounting and included in Alternative Energy Partnership Investments in the Condensed Consolidated Balance Sheets. The Company uses the HLBV equity method to account for earnings and losses. This method provides an earnings allocation that appropriately reflects the substantive economics of the investment. Earnings and losses on the investment are reported in Change in Value of Alternative Energy Partnership Investments and investment tax credits are recognized in Income Tax Benefit on the Condensed Consolidated Statements of Income (Loss). Note 9 - Variable Interest Entities (Continued) The following table presents information regarding activity in the Company’s Alternative Energy Partnership Investments for the three months ended March 31, 2024 and 2023. Three Months Ended (Dollars in Millions) Mar 31, 2024 Mar 31, 2023 Cash distribution from Investment 0.5 0.5 Income on Investments in Alternative Energy Partnership 0.4 0.7 Income Tax Credits (Recaptures) Recognized — (0.1) Tax Expense Recognized from Alternative Energy Partnership (0.1) (0.2) The following table represents the carrying value of the associated assets and liabilities and the associated maximum loss exposure of the Alternative Energy Partnership Investments as of March 31, 2024 and December 31, 2023. (Dollars in Millions) Mar 31, 2024 Dec 31, 2023 Cash $ 2.7 $ 2.7 Equipment, Net of Depreciation 255.0 256.2 Other Assets 7.5 7.5 Total Unconsolidated Assets 265.2 266.4 Maximum Loss Exposure 17.2 17.3 The Company’s maximum loss exposure in the event that all of the assets in the Alternative Energy Partnership are deemed worthless is $17.2 million and $17.3 million, which is the carrying value of the investment at March 31, 2024 and December 31, 2023, respectively.

Deferred Costs, Capitalized, Pr

Deferred Costs, Capitalized, Prepaid, and Other Assets	3 Months Ended
Deferred Costs, Capitalized, Prepaid, and Other Assets	Mar. 31, 2024
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Deferred Policy Acquisition Costs	Deferred Policy Acquisition Costs The following table presents the balances and changes in Deferred Policy Acquisition Costs for the Property and Casualty and Life and Health and business for the three months ended March 31, 2024 and 2023: March 31, 2024 March 31, 2023 Property and Casualty Life and Health Total Property and Casualty Life and Health Total Balance, Beginning of Year $ 164.9 $ 426.7 $ 591.6 $ 231.1 $ 404.5 $ 635.6 Capitalizations 120.0 15.8 135.8 149.5 15.4 164.9 Amortization Expense (125.4) (5.3) (130.7) (142.3) (5.6) (147.9) Experience Adjustment — (1.4) (1.4) — (1.1) (1.1) Balance, End of Period $ 159.5 $ 435.8 $ 595.3 $ 238.3 $ 413.2 $ 651.5 Costs directly associated with the successful acquisition of business, principally commissions and certain premium taxes and policy issuance costs, are deferred. Costs deferred on property and casualty insurance contracts are amortized over the period in which premiums are earned. Costs deferred on traditional life insurance products and other long-duration insurance contracts are amortized on a constant level basis over the expected life of the contracts in accordance with the assumptions used to estimate the liability for future policyholder benefits for nonparticipating traditional and limited-payment contracts. The underlying assumptions for deferred policy acquisition costs and the liability for future policyholder benefits are updated concurrently. The Company did not make any changes to future assumptions for the three months ended March 31, 2024 and 2023.

Receivables from Policyholders

Receivables from Policyholders - Allowance for Expected Credit Losses	3 Months Ended
	Mar. 31, 2024
Credit Loss [Abstract]
Receivables from Policyholders - Allowance for Expected Credit Losses	Receivables from Policyholders - Allowance for Expected Credit Losses The following tables present the balances of Receivables from Policyholders, net of the allowance for expected credit losses, as of March 31, 2024 and 2023, and a rollforward of changes in the allowance for expected credit losses for the three months ended March 31, 2024 and 2023. Three Months Ended March 31, 2024 (Dollars in Millions) Specialty Life Total Segments Non-Core Operations Total Allowance for Expected Credit Losses Balance, Beginning of Year $ 12.9 $ — $ 12.9 $ 1.0 $ 13.9 Provision for Expected Credit Losses 6.2 0.1 6.3 0.2 6.5 Write-offs of Uncollectible Receivables from Policyholders (13.7) (0.1) (13.8) (0.2) (14.0) Balance, End of Period $ 5.4 $ — $ 5.4 $ 1.0 $ 6.4 Receivable Balance, End of Period $ 892.8 $ 10.5 $ 903.3 $ 49.8 $ 953.1 Three Months Ended March 31, 2023 (Dollars in Millions) Specialty Life Total Segments Non-Core Operations Total Allowance for Expected Credit Losses Balance, Beginning of Year $ 12.3 $ — $ 12.3 $ 0.8 $ 13.1 Provision for Expected Credit Losses 10.3 0.3 10.6 0.4 11.0 Write-offs of Uncollectible Receivables from Policyholders (12.0) (0.3) (12.3) (0.5) (12.8) Balance, End of Period $ 10.6 $ — $ 10.6 $ 0.7 $ 11.3 Receivable Balance, End of Period $ 1,232.7 $ 9.7 $ 1,242.4 $ 101.6 $ 1,344.0

Other Comprehensive Income and

Other Comprehensive Income and Accumulated Other Comprehensive Loss	3 Months Ended
	Mar. 31, 2024
Statement of Comprehensive Income [Abstract]
Other Comprehensive Income and Accumulated Other Comprehensive Loss	Other Comprehensive Income and Accumulated Other Comprehensive Loss The tables below display the changes in Accumulated Other Comprehensive Loss by component for the three months ended March 31, 2024 and 2023. (Dollars in Millions) Net Unrealized Losses on Other Investments Net Unrealized Losses on Investments with an Allowance for Credit Losses Net Unrecognized Postretirement Benefit Income Gain on Cash Flow Hedges Change in Discount Rate on Future Life Policyholder Benefits Total Balance as of January 1, 2024 $ (530.9) $ (2.5) $ 9.5 $ 2.5 $ 160.6 (360.8) Other Comprehensive (Loss) Income Before Reclassifications (96.1) 1.6 — — 111.5 17.0 Amounts Reclassified from Accumulated Other Comprehensive Loss Net of Tax (Expense) Benefit of $(2.6), $0.2, $0.1, $0.0, $0.0 and $(2.3) 9.8 (0.2) (0.8) — — 8.8 Other Comprehensive (Loss) Income Net of Tax Benefit (Expense) of $22.7, $0.1, $0.1, $0.0, $(29.6), and $(6.7) (86.3) 1.4 (0.8) — 111.5 25.8 Balance as of March 31, 2024 $ (617.2) $ (1.1) $ 8.7 $ 2.5 $ 272.1 $ (335.0) (Dollars in Millions) Net Unrealized Losses on Other Investments Net Unrealized Losses on Investments with an Allowance for Credit Losses Net Unrecognized Postretirement Benefit Costs Gain (Loss) on Cash Flow Hedges Change in Discount Rate on Future Life Policyholder Benefits Total Balance as of January 1, 2023 $ (719.4) $ (2.2) $ (37.2) $ 2.8 $ 241.1 $ (514.9) Other Comprehensive Income (Loss) Before Reclassifications 147.5 1.4 — — (86.7) 62.2 Amounts Reclassified from Accumulated Other Comprehensive Loss Net of Tax Benefit (Expense) of $0.0, $0.4, $(0.1), $0.1, $0.0 and $0.4 (0.1) (1.4) (0.4) (0.1) — (2.0) Other Comprehensive Income (Loss) Net of Tax (Expense) Benefit of $(39.8), $(0.4), $0.0, $0.0, $23.1, and $(17.1) 147.4 — (0.4) (0.1) (86.7) 60.2 Balance as of March 31, 2023 $ (572.0) $ (2.2) $ (37.6) $ 2.7 $ 154.4 $ (454.7) Amounts reclassified from Accumulated Other Comprehensive Loss shown above are reported in Net Income (Loss) as follows: Components of AOCI Condensed Consolidated Statements of Income (Loss) Line Item Affected by Reclassifications Net Unrealized Losses on Other Investments and Net Unrealized Losses on Investments with an Allowance for Credit Losses Net Realized Investment Gains and Impairment Losses Net Unrecognized Postretirement Benefit Income (Costs) Policyholders’ Benefits and Incurred Losses and Loss Adjustment Expenses, Insurance Expenses, and Interest and Other Expenses Gain (Loss) on Cash Flow Hedges Interest and Other Expenses

Stockholders_ Equity

Stockholders’ Equity	3 Months Ended
Stockholders’ Equity	Mar. 31, 2024
Stockholders' Equity Note [Abstract]
Stockholders' Equity	Shareholders’ Equity Common Stock Repurchases On May 6, 2020, Kemper’s Board of Directors authorized the repurchase of up to an additional $200.0 million of Kemper common stock, in addition to the $133.3 million remaining under the August 6, 2014 authorization, bringing the remaining Note 13 - Shareholders’ Equity (Continued) share repurchase authorization to approximately $333.3 million. As of March 31, 2024, the remaining share repurchase authorization was $171.6 million under the repurchase program. During the three months ended March 31, 2024 and 2023, Kemper did not repurchase any of its common stock. Employee Stock Purchase Plan During the three months ended March 31, 2024 and 2023, the Company issued 15,000 and 18,000 shares under the Kemper Employee Stock Purchase Plan (“ESPP”), respectively, at an average discounted price of $52.63 and $46.46 per share. Compensation costs charged against income were $0.1 million and $0.2 million for the three months ended March 31, 2024 and 2023, respectively.

Policyholder Contract Liabiliti

Policyholder Contract Liabilities	3 Months Ended
Policyholder Contract Liabilities	Mar. 31, 2024
Insurance [Abstract]
Policyholder Contract Liabilities	Policyholder Obligations Policyholder Obligations at March 31, 2024 and December 31, 2023 were as follows: (Dollars in Millions) Mar 31, Dec 31, FHLB Funding Agreements $ 563.2 $ 557.4 Universal Life-type Policyholder Account Balances 97.7 98.3 Total $ 660.9 $ 655.7 FHLB Funding Agreements Kemper’s subsidiary, United Insurance Company of America (“United Insurance”) has entered into funding agreements with the FHLB of Chicago in exchange for cash, which it uses for spread lending purposes. During the three months ended March 31, 2024, United Insurance received advances of $25.0 million from the FHLB of Chicago and made repayments of $19.2 million under the spread lending program. When a funding agreement is issued, United Insurance is then required to post collateral in the form of eligible securities including mortgage-backed, government, and agency debt instruments for each of the advances that are entered. The fair value of the collateral pledged must be maintained at certain specified levels above the borrowed amount, which can vary depending on the assets pledged. If the fair value of the collateral declines below these specified levels of the amount borrowed, United Insurance would be required to pledge additional collateral or repay outstanding borrowings. Upon any event of default by United Insurance, the FHLB’s recovery on the collateral is limited to the amount of United Insurance’s liability under the funding agreements to the FHLB of Chicago. United Insurance’s liability under the funding agreements with the FHLB of Chicago, the amount of collateral pledged under such agreements and FHLB of Chicago common stock owned by United Insurance at March 31, 2024 and December 31, 2023 is presented below. (Dollars in Millions) Mar 31, Dec 31, Liability under Funding Agreements $ 563.2 $ 557.4 Fair Value of Collateral Pledged 712.1 629.3 FHLB of Chicago Common Stock Owned at Cost 16.3 16.6 Universal Life-type Policyholder Account Balances The Company’s weighted-average crediting rate for Universal Life-type Policyholder Account Balances was 5.1% as of March 31, 2024 and 2023. Guaranteed minimum benefit amounts in excess of the current account balances for these contracts were $289.2 million and $294.1 million

Debt

Debt	3 Months Ended
Debt	Mar. 31, 2024
Debt Disclosure [Abstract]
Debt	Debt Amended and Extended Credit Agreement On March 15, 2022, the Company entered into an amended and extended credit agreement. The amended and extended credit agreement increased the borrowing capacity of the existing unsecured credit agreement to $600.0 million and extended the maturity date to March 15, 2027. Furthermore, the amended and extended credit agreement provides for an accordion feature whereby the Company can increase the revolving credit borrowing capacity by an additional $200.0 million for a total maximum capacity of $800.0 million. Financial covenants within the agreement limit the Company from accessing the maximum capacity. The amount available as of March 31, 2024 was $424.0 million. There were no outstanding borrowings under the credit agreement at either March 31, 2024 or December 31, 2023. Long-term Debt The Company designates debt obligations as either short-term or long-term based on maturity date at issuance. Total amortized cost of Long-term Debt, Current and Non-Current, outstanding at March 31, 2024 and December 31, 2023 was: (Dollars in Millions) Mar 31, Dec 31, Senior Notes: Current: 4.350% Senior Notes due February 15, 2025 $ 449.7 $ — Non-Current: 4.350% Senior Notes due February 15, 2025 — 449.6 2.400% Senior Notes due September 30, 2030 397.1 397.0 3.800% Senior Notes due February 23, 2032 396.1 396.0 5.875% Fixed-Rate Reset Junior Subordinated Debentures due 2062 146.9 146.6 Total Long-term Debt Outstanding $ 1,389.8 $ 1,389.2 4.350% Senior Notes Due 2025 Kemper has $450.0 million aggregate principal of 4.350% senior notes due February 15, 2025 (the “2025 Senior Notes”). Kemper initially issued $250.0 million of the notes in February of 2015 and issued an additional $200.0 million of the notes in June of 2017. The additional notes are fungible with the initial notes issued in 2015, and together are treated as part of a single series for all purposes under the indenture governing the 2025 Senior Notes. The 2025 Senior Notes are unsecured and may be redeemed in whole at any time or in part from time to time at Kemper’s option at specified redemption prices. As of March 31, 2024, the 2025 Senior Notes have been classified as Current due to the notes reaching maturity within 12 months of the financial statement date. 2.400% Senior Notes Due 2030 Kemper has $400.0 million aggregate principal of 2.400% senior notes due September 30, 2030 (the “2030 Senior Notes”). The net proceeds of issuance were $395.8 million, net of discount and transaction costs for an effective yield of 2.52%. The 2030 Senior Notes are unsecured and may be redeemed in whole at any time or in part from time to time, at Kemper’s option, at specified redemption prices. 3.800% Senior Notes Due 2032 On February 15, 2022, Kemper offered and sold $400.0 million aggregate principal of 3.800% senior notes due February 23, 2032 (the “2032 Senior Notes”). The net proceeds of issuance were $395.1 million, net of discount and transaction costs, for an effective yield of 3.950%. The 2032 Senior Notes are unsecured and may be redeemed in whole at any time or in part from time to time, at Kemper’s option, at specified redemption prices. In anticipation of the issuance of the 2032 Senior Notes and for risk management purposes, the Company entered into a derivative transaction to hedge the risk of changes in the debt cash flows attributable to changes in the benchmark U.S. Note 15 - Debt (Continued) Treasury interest rate during the period leading up to the debt issuance (“Treasury Lock”). The effective portion of the gain on the derivative instrument upon discontinuance was $5.9 million before taxes, and is reported as a component of Accumulated Other Comprehensive Loss. Beginning with the issuance of the 2032 Senior Notes described in the preceding paragraph, such gain is being amortized into earnings and reported in Interest and Other Expenses in the same periods that the hedged items affect earnings. Amortization, reported in Interest and Other Expenses, was $0.1 million for the three months ended March 31, 2024 and 2023. The Company expects to reclassify $0.5 million of net gain on derivative instruments from AOCI to earnings for the twelve months ended March 31, 2025 as interest expense on the debt is recognized. 5.875% Fixed-Rate Reset Junior Subordinated Debentures Due 2062 On March 10, 2022, Kemper issued $150.0 million aggregate principal amount of 5.875% Fixed-Rate Reset Junior Subordinated Debentures due March 15, 2062 (the “2062 Junior Debentures”). The net proceeds from issuance were $144.7 million, net of discount and transaction costs. The 2062 Junior Debentures will bear interest from and including the date of original issue to, but excluding, March 15, 2027 (the “First Reset Date”) at the fixed rate of 5.875% per annum. The interest rate on the First Reset Date, and subsequent Reset Dates, will be equal to the Five-Year Treasury Rate as of the most recent Reset Date plus 4.140% to be reset on each Reset Date. Interest is due quarterly in arrears beginning on June 15, 2022. The Company has the option to defer interest payments for one or more optional deferral periods of up to five The 2062 Junior Debentures are unsecured and may be redeemed in whole or in part on the First Reset Date or any time thereafter, at a redemption price equal to the principal amount of the debentures being redeemed plus any accrued and unpaid interest. Short-term Debt Kemper’s subsidiaries, United Insurance, Trinity Universal Insurance Company (“Trinity”) and American Access Casualty Company (“AAC”), are members of the FHLBs of Chicago, Dallas and Chicago, respectively. As a requirement of membership in the FHLBs, United Insurance, Trinity, and AAC maintain a certain level of investment in FHLB stock. The Company periodically uses short-term FHLB borrowings for cash management and risk management purposes, in addition to long-term FHLB borrowings for the spread lending program. There were no short-term debt advances from the FHLBs of Chicago or Dallas outstanding at March 31, 2024 or December 31, 2023. For information on United Insurance’s funding agreement with the FHLB of Chicago in connection with the spread lending program, see Note 14, “Policyholder Obligations,” to the Condensed Consolidated Financial Statements. Interest Expense and Interest Paid

Leases

Leases	3 Months Ended
Leases	Mar. 31, 2024
Leases [Abstract]
Leases	Leases The Company leases certain office space under non-cancelable operating leases, with initial terms typically ranging from one one The following table presents operating lease right-of-use assets and lease liabilities. (Dollars in Millions) Mar 31, Dec 31, Operating Lease Right-of-Use Assets $ 36.1 $ 38.4 Operating Lease Liabilities 58.3 62.3 Note 16 - Leases (Continued) Lease expenses are primarily included in insurance expenses in the Condensed Consolidated Statements of Income (Loss). Additional information regarding the Company’s operating leases is presented below. Three Months Ended (Dollars in Millions) Mar 31, Mar 31, Lease Cost: Operating Lease Cost $ 3.9 $ 4.1 Variable Lease Cost 1.1 0.1 Short-Term Lease Cost 1 — — Total Lease Expense $ 5.0 $ 4.2 Total Lease Cost $ 5.0 $ 4.2 1 Leases with an initial term of twelve months or less are not recorded on the Condensed Consolidated Balance Sheets. Other Information on Operating Leases Significant judgments and assumptions for determining lease asset and liability at March 31, 2024 and 2023 are presented below. Three Months Ended Mar 31, Mar 31, Weighted-average Remaining Lease Term - Operating Leases 5.5 years 5.6 years Weighted-average Discount Rate - Operating Leases 4.3 % 3.6 % Most of the Company’s leases do not provide an implicit rate. Accordingly, the Company uses its incremental borrowing rate based on the information available at the commencement date to determine its lease payments’ present value. Future minimum lease payments under operating leases at March 31, 2024 are presented below. (Dollars in Millions) March 31, 2024 Remainder of 2024 $ 15.0 2025 15.7 2026 9.7 2027 7.4 2028 4.7 2029 and Thereafter 15.2 Total Future Payments $ 67.7 Less: Discount 9.4 Present Value of Minimum Lease Payments $ 58.3 As of March 31, 2024 and December 31, 2023, the Company did not have any finance leases.
Leases	Leases The Company leases certain office space under non-cancelable operating leases, with initial terms typically ranging from one one The following table presents operating lease right-of-use assets and lease liabilities. (Dollars in Millions) Mar 31, Dec 31, Operating Lease Right-of-Use Assets $ 36.1 $ 38.4 Operating Lease Liabilities 58.3 62.3 Note 16 - Leases (Continued) Lease expenses are primarily included in insurance expenses in the Condensed Consolidated Statements of Income (Loss). Additional information regarding the Company’s operating leases is presented below. Three Months Ended (Dollars in Millions) Mar 31, Mar 31, Lease Cost: Operating Lease Cost $ 3.9 $ 4.1 Variable Lease Cost 1.1 0.1 Short-Term Lease Cost 1 — — Total Lease Expense $ 5.0 $ 4.2 Total Lease Cost $ 5.0 $ 4.2 1 Leases with an initial term of twelve months or less are not recorded on the Condensed Consolidated Balance Sheets. Other Information on Operating Leases Significant judgments and assumptions for determining lease asset and liability at March 31, 2024 and 2023 are presented below. Three Months Ended Mar 31, Mar 31, Weighted-average Remaining Lease Term - Operating Leases 5.5 years 5.6 years Weighted-average Discount Rate - Operating Leases 4.3 % 3.6 % Most of the Company’s leases do not provide an implicit rate. Accordingly, the Company uses its incremental borrowing rate based on the information available at the commencement date to determine its lease payments’ present value. Future minimum lease payments under operating leases at March 31, 2024 are presented below. (Dollars in Millions) March 31, 2024 Remainder of 2024 $ 15.0 2025 15.7 2026 9.7 2027 7.4 2028 4.7 2029 and Thereafter 15.2 Total Future Payments $ 67.7 Less: Discount 9.4 Present Value of Minimum Lease Payments $ 58.3 As of March 31, 2024 and December 31, 2023, the Company did not have any finance leases.

Income Taxes

Income Taxes	3 Months Ended
Income Taxes	Mar. 31, 2024
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes The statute of limitations related to Kemper and its eligible subsidiaries’ consolidated Federal income tax returns is closed for all tax years up to and including 2011 as well as 2018 and 2019. As a result of the Company filing amended federal income tax returns, tax years 2012 and 2013 are under limited examination with respect to carryback adjustments associated with the amended returns. The statute of limitations related to tax years 2014, 2015, 2016 and 2017 has been extended to December 31, 2024. Tax years 2020, 2021 and 2022 are subject to a statute of three years from the extended due dates of October 15, 2021, 2022 and 2023, respectively. Note 17 - Income Taxes (Continued) The expiration of the statute of limitations related to the various state income tax returns that Kemper and its subsidiaries file varies by state. The interim period tax expense or benefit is the difference between the year-to-date income tax provision and the amounts reported for the previous interim periods of the fiscal year. For the three months ended March 31, 2024 the income tax expense attributable to Kemper Corporation was $16.8 million, or 19.1% of income before income taxes, compared to an income tax benefit of $23.8 million, or 22.9% of loss before income taxes for the three months ended March 31, 2023. There were no Unrecognized Tax Benefits at March 31, 2024, or December 31, 2023. The Company recognizes interest and penalties, if any, related to unrecognized tax benefits in Income Tax (Expense) Benefit. There were no liabilities for accrued interest and penalties for the three months ended March 31, 2024 and 2023. For the three months ended March 31, 2024 and 2023, federal income tax refunds received, net of income taxes paid, were $10.4 million and $124.7 million, respectively. For the three months ended March 31, 2024 and 2023, state income taxes paid, net of refunds received, were negligible. No foreign income taxes were paid or refunded for the three months ended March 31, 2024 and March 31, 2023, respectively.

Commitments and Contingencies

Commitments and Contingencies	3 Months Ended
Commitments and Contingencies	Mar. 31, 2024
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies In the ordinary course of its businesses, the Company is involved in legal proceedings including lawsuits, arbitration, regulatory examinations, audits and inquiries. Based on currently available information, the Company does not believe that it is reasonably possible that any of its pending legal proceedings will have a material effect on the Company’s Condensed Consolidated Financial Statements and Notes to the Condensed Consolidated Financial Statements.

Pay vs Performance Disclosure

Pay vs Performance Disclosure - USD ($) $ in Millions	3 Months Ended
Pay vs Performance Disclosure - USD ($) $ in Millions	Mar. 31, 2024	Mar. 31, 2023
Pay vs Performance Disclosure
Net Income (Loss)	$ 71.3	$ (80.1)

Insider Trading Arrangements

Insider Trading Arrangements	3 Months Ended
Insider Trading Arrangements	Mar. 31, 2024
Trading Arrangements, by Individual
Rule 10b5-1 Arrangement Adopted	false
Non-Rule 10b5-1 Arrangement Adopted	false
Rule 10b5-1 Arrangement Terminated	false
Non-Rule 10b5-1 Arrangement Terminated	false

Basis of Presentation and Acc_2

Basis of Presentation and Accounting Policies (Policies)	3 Months Ended
Basis of Presentation and Accounting Policies (Policies)	Mar. 31, 2024
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Adoption of New Accounting Guidance and Guidance Not Yet Adopted	Adoption of New Accounting Guidance The Company has adopted all recently issued accounting pronouncements with effective dates prior to March 31, 2024. Guidance Adopted in 2024 In March 2023, the FASB issued ASU 2023-02 Accounting for Investments in Tax Credit Structures Using the Proportional Amortization Method , which expands the use of the proportional amortization method of accounting to equity investments in other tax credit structures that meet certain criteria. The proportional amortization method results in the tax credit investment being amortized in proportion to the allocation of tax credits and other tax benefits in each period, and a net presentation within the income tax line item. ASU 2023-02 is effective for annual periods beginning after December 15, 2023 and interim periods within those annual periods. The Company adopted the new standard on January 1, 2024. The adoption did not have a material impact on the Company's Condensed Consolidated Financial Statements. Guidance Not Yet Adopted In October 2023, the FASB issued ASU 2023-06 Disclosure Improvements: Codification Amendments in Response to the SEC’s Disclosure Update and Simplification Initiative. This ASU amends the disclosure or presentation requirements related to various subtopics in the FASB Accounting Standards Codification. For SEC registrants, the effective date for each amendment will be the date on which the SEC’s removal of that related disclosure requirement from Regulation S-X or Regulation S-K becomes effective, with early adoption prohibited. The Company will monitor the removal of various requirements from the current regulations in order to determine when to adopt the related amendments, but does not anticipate the adoption of the new guidance will have a material impact on the Company’s Condensed Consolidated Financial Statements. The Company will continue to evaluate the impact of this guidance on its consolidated financial statements. In November 2023, the FASB issued ASU 2023-07 Improvements to Reportable Segment Disclosures , which enhances disclosures about significant segment expenses. The new standard does not change the definition or aggregation of operating segments but will add required disclosures of significant expenses for each reportable segment as well as certain other disclosures to help financial statement users understand how the chief operating decision maker evaluates segment expenses and operating results. ASU 2023-07 is effective for annual periods beginning after December 15, 2023 and interim periods within fiscal years beginning after December 15, 2024. The Company is currently evaluating the impact of this guidance on its consolidated financial statements. Note 1 - Basis of Presentation and Accounting Policies (Continued) In December 2023, the FASB issued ASU 2023-09 Improvements to Income Tax Disclosures , which improves the transparency of income tax disclosures by requiring companies to use consistent categories and greater disaggregation of information in the tax rate reconciliation as well as requiring disaggregation of income taxes paid by jurisdiction. ASU 2023-09 is effective for annual periods beginning after December 15, 2024, with early adoption permitted for annual financial statements that have not yet been issued or made available for issuance. The Company is currently evaluating the impact of this guidance on its consolidated financial statements. In March 2024, the SEC adopted a final rule requiring registrants to disclose certain climate-related information in their registration statements and annual reports. The rule requires the disclosure of qualitative and quantitative information, with certain information, such as financial statement effects of severe weather events, included in the notes to the audited financial statements. Other disclosure requirements include material climate-related risks, processes to manage and govern those risks, disclosure of targets if the targets materially affect or are reasonably likely to materially affect the Company, and, if material, disclosure of certain greenhouse gas emissions. On April 4, 2024, the SEC issued a voluntary stay of the final rule, pending the outcome of pending litigation. The requirements will be applied prospectively and have phased-in effective dates. For the Company, the Form 10-K for the year ended December 31, 2025, will be the first annual report with new climate-related disclosures. The Company is currently evaluating the impact of adopting the final rule.

Net Income (Loss) Per Unrestr_2

Net Income (Loss) Per Unrestricted Share (Tables)	3 Months Ended
Net Income (Loss) Per Unrestricted Share (Tables)	Mar. 31, 2024
Earnings Per Share [Abstract]
Schedule of Calculation of Numerator and Denominator in Earnings Per Share	Net Income (Loss) Per Unrestricted Share and Diluted Net Income (Loss) Per Unrestricted Share for the three months ended March 31, 2024 and 2023 is presented below. Three Months Ended (Dollars in Millions, except per share amounts) Mar 31, Mar 31, Net Income (Loss) attributable to Kemper Corporation $ 71.3 $ (80.1) Shares in Thousands Weighted-average Unrestricted Shares Outstanding 64,254.5 63,946.6 Equity-based Compensation Equivalent Shares 518.3 — Weighted-average Unrestricted Shares and Equivalent Shares Outstanding Assuming Dilution 64,772.8 63,946.6 Net Income (Loss) attributable to Kemper Corporation per Unrestricted Share: (Per Unrestricted Share in Whole Dollars) Basic Net Income (Loss) Per Unrestricted Share $ 1.11 $ (1.25) Diluted Net Income (Loss) Per Unrestricted Share $ 1.10 $ (1.25)

Business Segments (Tables)

Business Segments (Tables)	3 Months Ended
Business Segments (Tables)	Mar. 31, 2024
Segment Reporting [Abstract]
Revenue from External Customers by Products and Services	Earned Premiums by product line, including a reconciliation to Total Earned Premiums, for the three months ended March 31, 2024 and 2023 were: Three Months Ended (Dollars in Millions) Mar 31, Mar 31, Specialty Property & Casualty Insurance: Personal Automobile $ 675.3 $ 787.9 Commercial Automobile 164.7 156.3 Life Insurance: Life 80.6 82.2 Accident and Health 5.6 5.9 Property 11.1 11.2 Total Segment Earned Premiums 937.3 1,043.5 Non-Core Operations 94.6 137.4 Total Earned Premiums $ 1,031.9 $ 1,180.9
Reconciliation of Revenue from Segments to Consolidated	Segment Revenues, including a reconciliation to Total Revenues, for the three months ended March 31, 2024 and 2023 were: Three Months Ended (Dollars in Millions) Mar 31, Mar 31, Segment Revenues: Specialty Property & Casualty Insurance: Earned Premiums $ 840.0 $ 944.2 Net Investment Income 41.1 38.5 Change in Value of Alternative Energy Partnership Investments 0.3 0.4 Other Income 1.1 0.9 Total Specialty Property & Casualty Insurance 882.5 984.0 Life Insurance: Earned Premiums 97.3 99.3 Net Investment Income 44.3 49.8 Change in Value of Alternative Energy Partnership Investments 0.1 0.2 Other Income (Loss) 0.2 (0.4) Total Life Insurance 141.9 148.9 Total Segment Revenues 1,024.4 1,132.9 Change in Fair Value of Equity and Convertible Securities 3.4 1.7 Net Realized Investment Gains 6.6 6.4 Net Impairment Losses Recognized in Earnings (1.5) 2.1 Non-Core Operations 106.2 148.0 Other 3.9 3.7 Total Revenues $ 1,143.0 $ 1,294.8
Reconciliation of Operating Profit (Loss) from Segments to Consolidated	Adjusted Consolidated Operating Income (Loss), including a reconciliation to Income (Loss) before Income Taxes attributable to Kemper Corporation, for the three months ended March 31, 2024 and 2023 was: Three Months Ended (Dollars in Millions) Mar 31, Mar 31, Segment Adjusted Operating Income (Loss): Specialty Property & Casualty Insurance $ 86.5 $ (74.7) Life Insurance 14.0 14.8 Total Segment Adjusted Operating Income (Loss) 100.5 (59.9) Corporate and Other Adjusted Operating Loss (15.6) (12.9) Less: (Loss) Income before Income Taxes attributable to Noncontrolling Interest (1.4) — Adjusted Consolidated Operating Income (Loss) 86.3 (72.8) Income (Loss) From: Change in Fair Value of Equity and Convertible Securities 3.4 1.7 Net Realized Investment Gains 6.6 6.4 Impairment Losses (1.5) 2.1 Acquisition and Disposition Related Transaction, Integration, Restructuring and Other Costs (12.8) (29.1) Non-Core Operations 6.0 (12.2) Income (Loss) before Income Taxes attributable to Kemper Corporation $ 88.0 $ (103.9)
Reconciliation of Other Significant Reconciling Items from Segments to Consolidated	Adjusted Consolidated Net Operating Income (Loss), including a reconciliation to Net Income (Loss) attributable to Kemper Corporation, for the three months ended March 31, 2024 and 2023 was: Three Months Ended (Dollars in Millions and Net of Income Taxes) Mar 31, Mar 31, Segment Adjusted Net Operating Income (Loss): Specialty Property & Casualty Insurance $ 69.2 $ (58.4) Life Insurance 11.9 13.2 Total Segment Adjusted Net Operating Income (Loss) 81.1 (45.2) Corporate and Other Adjusted Net Operating Loss (12.5) (10.5) Less: Net (Loss) Income attributable to Noncontrolling Interest (1.1) — Adjusted Consolidated Net Operating Income (Loss) 69.7 (55.7) Net Income (Loss) From: Change in Fair Value of Equity and Convertible Securities 2.7 1.3 Net Realized Investment Gains 5.2 5.1 Impairment Losses (1.2) 1.7 Acquisition and Disposition Related Transaction, Integration, Restructuring and Other Costs (10.1) (23.0) Non-Core Operations 5.0 (9.5) Net Income (Loss) attributable to Kemper Corporation $ 71.3 $ (80.1)

Property and Casualty Insuran_2

Property and Casualty Insurance Reserves (Tables)	3 Months Ended
Property and Casualty Insurance Reserves (Tables)	Mar. 31, 2024
Liability for Future Policy Benefits and Unpaid Claims and Claims Adjustment Expense [Abstract]
Liability for Unpaid Claims Adjustment Expense by Expense Type	three months ended March 31, 2024 and 2023 was: Three Months Ended (Dollars in Millions) Mar 31, Mar 31, Property and Casualty Insurance Reserves: Gross of Reinsurance at Beginning of Year $ 2,680.5 $ 2,756.9 Less Reinsurance Recoverables at Beginning of Year 27.8 39.6 Property and Casualty Insurance Reserves, Net of Reinsurance at Beginning of Year 2,652.7 2,717.3 Incurred Losses and LAE related to: Current Year 686.1 944.0 Prior Years 8.8 41.9 Total Incurred Losses and LAE 694.9 985.9 Paid Losses and LAE related to: Current Year 213.9 325.5 Prior Years 562.9 690.9 Total Paid Losses and LAE 776.8 1,016.4 Property and Casualty Insurance Reserves, Net of Reinsurance at End of Period 2,570.8 2,686.8 Plus Reinsurance Recoverables at End of Period 26.4 34.3 Property and Casualty Insurance Reserves, Gross of Reinsurance at End of Period $ 2,597.2 $ 2,721.1

Liability for Future Policyho_2

Liability for Future Policyholder Benefits (Tables)	3 Months Ended
Liability for Future Policyholder Benefits (Tables)	Mar. 31, 2024
Insurance [Abstract]
Liability for Future Policy Benefit, Activity	The following tables summarize balances and changes in the present value of expected net premiums, present value of expected future policyholder benefits and net liability for future policyholder benefits as of and for the three months ended March 31, 2024 and 2023: Three Months Ended (Dollars in Millions) Mar 31, 2024 Mar 31, 2023 Present Value of Expected Net Premiums Balance, Beginning of Year $ 675.4 $ 688.6 Beginning Balance at Original Discount Rate $ 694.7 $ 728.9 Effect of Changes in Cash Flow Assumptions — — Effect of Actual Variances from Expected Experience 5.3 0.7 Adjusted Beginning of Year Balance 700.0 729.6 Issuances 38.2 31.8 Interest Accrual 7.6 7.0 Net Premiums Collected (22.7) (23.9) Ending Balance at Original Discount Rate 723.1 744.5 Effect of Changes in Discount Rate Assumptions (33.0) (22.1) Balance, End of Period $ 690.1 $ 722.4 Present Value of Expected Future Policyholder Benefits Balance, Beginning of Year $ 3,613.2 $ 3,561.0 Beginning Balance at Original Discount Rate $ 3,835.9 $ 3,906.2 Effect of Changes in Cash Flow Assumptions — — Effect of Actual Variances From Expected Experience 5.5 0.3 Adjusted Beginning of Year Balance 3,841.4 3,906.5 Issuances 38.2 31.8 Interest Accrual 42.6 42.4 Benefit Payments (56.5) (63.8) Ending Balance at Original Discount Rate 3,865.7 3,916.9 Effect of Changes in Discount Rate Assumptions (377.5) (217.4) Balance, End of Period $ 3,488.2 $ 3,699.5 Net Liability for Future Policyholder Benefits $ 2,798.1 $ 2,977.1 Less: Reinsurance Recoverable — — Net Liability for Future Policyholder Benefits, After Reinsurance Recoverable $ 2,798.1 $ 2,977.1
Weighted-Average Liability Duration	The weighted-average liability duration of the liability for future policyholder benefits as calculated under current rates is as follows: Mar 31, 2024 Mar 31, 2023 Weighted-Average Liability Duration of the Liability for Future Policyholder Benefits (Years) 14.6 14.9
Reconciliation of Net Liability for Future Policyholder Benefits	The reconciliation of the net liability for future policyholder benefits to Life and Health Insurance Reserves in the Condensed Consolidated Balance Sheets is as follows: (Dollars in Millions) Mar 31, 2024 Mar 31, 2023 Net Liability for Future Policyholder Benefits $ 2,798.1 $ 2,977.1 Deferred Profit Liability 357.5 272.6 Other 1 138.7 149.9 Total Life and Health Insurance Reserves $ 3,294.3 $ 3,399.6 1 Other primarily consists of Accident and Health and Universal Life reserves
Undiscounted Expected Gross Premiums and Expected Future Benefit Payments	The amounts of expected undiscounted future benefit payments, expected undiscounted future gross premiums and expected discounted future gross premiums, is as follows: (Dollars in Millions) Mar 31, 2024 Mar 31, 2023 Expected Future Benefit Payments, undiscounted $ 10,225.9 $ 10,177.7 Expected Future Gross Premiums, undiscounted $ 4,136.0 $ 4,464.2 Expected Future Gross Premiums, discounted $ 2,758.3 $ 2,931.1
Liability for Future Policy Benefits Interest Expense and Premiums	The amount of revenue and interest recognized in the Condensed Consolidated Statements of Income (Loss) is as follows: Three Months Ended (Dollars in Millions) Mar 31, 2024 Mar 31, 2023 Gross Premiums or Assessments $ 101.3 $ 103.8 Interest Expense $ 35.0 $ 35.4
Weighted Average Interest Rate for Future Policyholder Benfits	The weighted-average interest rate is as follows: Mar 31, 2024 Mar 31, 2023 Interest Accretion Rate 4.55 % 4.55 % Current Discount Rate 5.40 % 5.05 %
Policyholder Account Balance	The balances of and changes in Deferred Profit Liability as of and for the periods indicated are as follows: Three Months Ended (Dollars in Millions) Mar 31, 2024 Mar 31, 2023 Balance, Beginning of Year $ 337.8 $ 253.6 Profits Deferred 41.8 43.0 Interest Accrual 4.0 3.0 Amortization (25.9) (27.0) Effect of Actual Variances from Expected Experience and Other Changes (0.2) — Balance, End of Period $ 357.5 $ 272.6

Investments (Tables)

Investments (Tables)	3 Months Ended
Investments (Tables)	Mar. 31, 2024
Debt Securities, Available-for-sale [Line Items]
Investments Classified by Contractual Maturity Date	The amortized cost and estimated fair values of the Company’s Investments in Fixed Maturities at March 31, 2024 by contractual maturity were: (Dollars in Millions) Amortized Cost Fair Value Due in One Year or Less $ 195.2 $ 190.8 Due after One Year to Five Years 896.7 867.5 Due after Five Years to Ten Years 1,062.2 924.1 Due after Ten Years 3,604.5 3,125.0 Mortgage- and Asset-backed Securities Not Due at a Single Maturity Date 1,803.5 1,664.2 Investments in Fixed Maturities $ 7,562.1 $ 6,771.6
Schedule of Unrealized Loss on Investments	An aging of unrealized losses on the Company’s Investments in Fixed Maturities at March 31, 2024 is presented below. Less Than 12 Months 12 Months or Longer Total (Dollars in Millions) Fair Unrealized Fair Unrealized Fair Unrealized Fixed Maturities: U.S. Government and Government Agencies and Authorities $ 46.5 $ (1.6) $ 393.0 $ (93.3) $ 439.5 $ (94.9) States and Political Subdivisions 165.0 (3.3) 962.0 (202.5) 1,127.0 (205.8) Foreign Governments 0.9 — 1.7 (0.6) 2.6 (0.6) Corporate Securities: Bonds and Notes 432.3 (11.5) 2,801.7 (436.5) 3,234.0 (448.0) Redeemable Preferred Stocks — — 7.6 (1.1) 7.6 (1.1) Collateralized Loan Obligations 231.6 (0.8) 246.7 (14.6) 478.3 (15.4) Other Mortgage- and Asset-backed 14.9 (0.1) 292.5 (42.2) 307.4 (42.3) Total Fixed Maturities $ 891.2 $ (17.3) $ 4,705.2 $ (790.8) $ 5,596.4 $ (808.1) An aging of unrealized losses on the Company’s Investments in Fixed Maturities at December 31, 2023 is presented below. Less Than 12 Months 12 Months or Longer Total (Dollars in Millions) Fair Unrealized Fair Unrealized Fair Unrealized Fixed Maturities: U.S. Government and Government Agencies and Authorities $ 52.0 $ (0.8) $ 401.6 $ (83.7) $ 453.6 $ (84.5) States and Political Subdivisions 112.9 (2.3) 928.3 (187.5) 1,041.2 (189.8) Foreign Governments — — 1.9 (0.6) 1.9 (0.6) Corporate Securities: Bonds and Notes 198.4 (5.5) 2,813.0 (378.3) 3,011.4 (383.8) Redeemable Preferred Stocks — — 7.9 (0.8) 7.9 (0.8) Collateralized Loan Obligations 38.8 (0.4) 747.7 (24.1) 786.5 (24.5) Other Mortgage- and Asset-backed 15.7 (0.1) 287.3 (46.2) 303.0 (46.3) Total Fixed Maturities $ 417.8 $ (9.1) $ 5,187.7 $ (721.2) $ 5,605.5 $ (730.3)
Schedule of Other Investments	The carrying values of the Company’s Other Investments at March 31, 2024 and December 31, 2023 were: (Dollars in Millions) Mar 31, Dec 31, Equity Securities at Modified Cost $ 24.7 $ 32.6 Real Estate at Depreciated Cost 93.9 94.7 Mortgage Loans 93.1 99.8 Other 1.9 14.8 Total Other Investments $ 213.6 $ 241.9
Debt Securities, Available-for-Sale, Allowance for Credit Loss	The Company monitors accrued interest and writes off amounts when they are not expected to be received. States and Political Subdivisions Corporate Bonds and Notes Total (Dollars in Millions) Balance, Beginning of Year $ 0.5 $ 7.7 $ 8.2 Reductions Due to Sales — (0.2) (0.2) Net Decrease in Allowance on Securities for which Expected Credit Losses were Previously Recognized — (0.3) (0.3) Balance, End of Period $ 0.5 $ 7.2 $ 7.7 Note 6 - Investments (Continued) The following table sets forth the change in allowance for credit losses on fixed maturities available-for-sale by major security type for the three months ended March 31, 2023. States and Political Subdivisions Corporate Bonds and Notes Total (Dollars in Millions) Balance, Beginning of Year $ 0.7 $ 8.9 $ 9.6 Additions for Securities for which No Previous Expected Credit Losses were — 0.3 0.3 Reductions Due to Sales — (1.9) (1.9) Net Increase (Decrease) in Allowance on Securities for which Expected Credit Losses were Previously Recognized 0.1 (0.7) (0.6) Balance, End of Period $ 0.8 $ 6.6 $ 7.4
Investment Income	Net Investment Income for the three months ended March 31, 2024 and 2023 was: Three Months Ended (Dollars in Millions) Mar 31, Mar 31, Investment Income: Interest on Fixed Income Securities 1,2 $ 79.8 $ 81.5 Dividends on Equity Securities Excluding Alternative Investments 2.8 1.0 Alternative Investments: Equity Method Limited Liability Investments (2.1) 1.1 Limited Liability Investments Included in Equity Securities 3.4 2.6 Total Alternative Investments 1.3 3.7 Short-term Investments 7.3 2.3 Loans to Policyholders 5.2 5.4 Real Estate 2.3 2.4 Company-Owned Life Insurance 7.1 8.8 Other 2.5 3.0 Total Investment Income 108.3 108.1 Investment Expenses: Real Estate 2.2 2.1 Other Investment Expenses 1,2 5.7 4.2 Total Investment Expenses 7.9 6.3 Net Investment Income $ 100.4 $ 101.8 1 In the first quarter of 2024, the Company changed its presentation of the details of investment performance to report interest expense incurred on Federal Home Loan Bank ("FHLB") borrowings as an offset to interest on fixed income securities since FHLB borrowings are used for spread lending purposes. The interest expense incurred on FHLB borrowings was previously reported within Other Investment Expenses. The prior period amounts presented above have been updated to reflect this change in presentation. 2 Reduced by interest expense incurred on FHLB borrowings used for spread lending purposes of $5.2 million and $4.7 million, for the three months ended March 31, 2024 and 2023, respectively.
Schedule of Realized Gain (Loss)	Gross gains and losses on sales of investments in fixed maturities and gains and losses associated with Ultra-Long Treasury Futures for the three months ended March 31, 2024 and 2023 were: Three Months Ended (Dollars in Millions) Mar 31, Mar 31, Fixed Maturities: Gains on Sales $ 12.8 $ 1.1 Losses on Sales (2.3) (3.3) (Losses) Gains on Hedging Activity (7.9) 8.4
Investments in Fixed Maturities
Debt Securities, Available-for-sale [Line Items]
Schedule of Available-for-sale Securities Reconciliation	The amortized cost and fair values of the Company’s Investments in Fixed Maturities at March 31, 2024 were: Amortized Gross Unrealized Allowance for Expected Credit Losses Fair Value (Dollars in Millions) Gains Losses U.S. Government and Government Agencies and Authorities $ 582.3 $ 1.0 $ (94.9) $ — $ 488.4 States and Political Subdivisions 1,552.3 9.9 (205.8) (0.5) 1,355.9 Foreign Governments 5.2 — (0.6) — 4.6 Corporate Securities: Bonds and Notes 4,077.8 13.0 (448.0) (7.2) 3,635.6 Redeemable Preferred Stocks 9.0 0.1 (1.1) — 8.0 Collateralized Loan Obligations 952.5 1.1 (15.4) — 938.2 Other Mortgage- and Asset-backed 383.0 0.2 (42.3) — 340.9 Investments in Fixed Maturities $ 7,562.1 $ 25.3 $ (808.1) $ (7.7) $ 6,771.6 The amortized cost and fair values of the Company’s Investments in Fixed Maturities at December 31, 2023 were: Amortized Gross Unrealized Allowance for Expected Credit Losses Fair Value (Dollars in Millions) Gains Losses U.S. Government and Government Agencies and Authorities $ 594.1 $ 1.9 $ (84.5) $ — $ 511.5 States and Political Subdivisions 1,575.9 16.3 (189.8) (0.5) 1,401.9 Foreign Governments 4.4 — (0.6) — 3.8 Corporate Securities: Bonds and Notes 4,046.8 35.5 (383.8) (7.7) 3,690.8 Redeemable Preferred Stocks 9.0 0.1 (0.8) — 8.3 Collateralized Loan Obligations 973.6 0.7 (24.5) — 949.8 Other Mortgage- and Asset-backed 362.0 0.1 (46.3) — 315.8 Investments in Fixed Maturities $ 7,565.8 $ 54.6 $ (730.3) $ (8.2) $ 6,881.9

Derivatives (Tables)

Derivatives (Tables)	3 Months Ended
Derivatives (Tables)	Mar. 31, 2024
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Schedule of Derivatives Instruments Statements of Financial Performance and Financial Position, Location	The following table presents the derivative instruments, primary underlying risk exposure, gross notional amount, and estimated fair value of the Company’s derivatives: March 31, 2024 December 31, 2023 (Dollars in Millions) Estimated Fair Value Estimated Fair Value Derivative Instrument Primary Underlying Risk Exposure Gross Notional Amount Assets Liabilities Gross Notional Amount Assets Liabilities Derivatives Designated as Hedging Instruments: Treasury Futures Interest Rate Risk $ 74.9 $ 1.2 $ — $ — $ — $ — Derivatives Not Designated or Not Qualifying as Hedging Instruments: Treasury Futures Interest Rate Risk $ — $ — $ — $ 149.7 $ 14.7 $ —
Schedule of Cash Flow Hedges Included in Accumulated Other Comprehensive Income (Loss)	The below table reflects the amounts of Gains (Losses) deferred into AOCI, net changes in amounts in AOCI associated with current hedging transactions, amounts subsequently reclassified into Net Income (Loss) through Net Realized Investment Gains (Losses) for derivatives qualifying as cash flow hedges for the three months ended March 31, 2024 and 2023. Three Months Ended (Dollars in Millions) Mar 31, Mar 31, Beginning of Year $ — $ (0.4) Gains (Losses) Deferred in AOCI 1.5 (0.4) Net Change in AOCI with Current Period Hedging Transactions (1.3) — Gains (Losses) Reclassified into Income — (0.5) Net Comprehensive Gains (Losses) from Cash Flow Hedges $ 0.2 $ (1.3)

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	3 Months Ended		9 Months Ended
Fair Value Measurements (Tables)	Mar. 31, 2024	Mar. 31, 2023	Sep. 30, 2023
Fair Value Disclosures [Abstract]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis	The valuation of assets and liabilities measured at fair value in Company’s Condensed Consolidated Balance Sheets at March 31, 2024 is summarized below. The Company had no material liabilities that are measured and reported at fair value. Fair Value Measurements (Dollars in Millions) Quoted Prices Significant Other Significant Measured at Net Asset Value Total Fair Value Assets: Fixed Maturities: U.S. Government and Government Agencies and Authorities $ 85.4 $ 403.0 $ — $ — $ 488.4 States and Political Subdivisions — 1,354.5 1.4 — 1,355.9 Foreign Governments — 4.6 — — 4.6 Corporate Securities: Bonds and Notes — 3,455.1 180.5 — 3,635.6 Redeemable Preferred Stock — 5.8 2.2 — 8.0 Collateralized Loan Obligations — 938.2 — — 938.2 Other Mortgage and Asset-backed — 335.8 5.1 — 340.9 Total Investments in Fixed Maturities 85.4 6,497.0 189.2 — 6,771.6 Equity Securities at Fair Value: Preferred Stocks: Finance, Insurance and Real Estate — 15.9 — — 15.9 Other Industries — 7.8 2.2 — 10.0 Common Stocks: Finance, Insurance and Real Estate 0.6 — — — 0.6 Other Industries 0.3 — 0.5 — 0.8 Other Equity Interests: Exchange Traded Funds 8.7 — — — 8.7 Limited Liability Companies and Limited Partnerships — — — 194.1 194.1 Total Investments in Equity Securities at Fair Value 9.6 23.7 2.7 194.1 230.1 Other Investments: Derivative Instrument Classified as Cash Flow Hedge — 1.2 — — 1.2 Total Assets $ 95.0 $ 6,521.9 $ 191.9 $ 194.1 $ 7,002.9	The valuation of assets and liabilities measured at fair value in the Company’s Consolidated Balance Sheets at December 31, 2023 is summarized below. The Company had no material liabilities that are measured and reported at fair value. Fair Value Measurements (Dollars in Millions) Quoted Prices Significant Other Significant Measured at Net Asset Value Total Fair Value Assets: Fixed Maturities: U.S. Government and Government Agencies and Authorities $ 98.8 $ 412.7 $ — $ — $ 511.5 States and Political Subdivisions — 1,401.8 0.1 — 1,401.9 Foreign Governments — 3.8 — — 3.8 Corporate Securities: Bonds and Notes — 3,513.7 177.1 — 3,690.8 Redeemable Preferred Stocks — 1.2 7.1 — 8.3 Collateralized Loan Obligations — 949.8 — — 949.8 Other Mortgage and Asset-backed — 310.6 5.2 — 315.8 Total Investments in Fixed Maturities 98.8 6,593.6 189.5 — 6,881.9 Equity Securities at Fair Value: Preferred Stocks: Finance, Insurance and Real Estate — 15.6 — — 15.6 Other Industries — 7.5 2.4 — 9.9 Common Stocks: Finance, Insurance and Real Estate 0.6 — — — 0.6 Other Industries 0.2 — 0.4 — 0.6 Other Equity Interests: Exchange Traded Funds 7.7 — — — 7.7 Limited Liability Companies and Limited Partnerships — — — 191.4 191.4 Total Investments in Equity Securities at Fair Value 8.5 23.1 2.8 191.4 225.8 Other Investments: Derivative Instruments Not Designated as Hedges — 14.7 — — 14.7 Total Assets $ 107.3 $ 6,631.4 $ 192.3 $ 191.4 $ 7,122.4
Fair Value Measurement Inputs and Valuation Techniques	The table below presents quantitative information about the significant unobservable inputs utilized by the Company in determining fair values for fixed maturity investments classified as Level 3 at March 31, 2024. Valuations for assets presented in the tables below are primarily based on broker/dealer quotes for which there is a lack of transparency as to inputs used to develop the valuations. The quantitative detail of these unobservable inputs is neither provided nor reasonably available to the Company. The weighted average yield is calculated based on fair value. (Dollars in Millions) Unobservable Input Total Fair Value Range of Unobservable Inputs Weighted-average Yield Investment-grade Market Yield $ 55.3 1.8 % - 13.5 % 7.9 % Non-investment-grade: Senior Debt Market Yield 31.7 7.0 - 48.0 13.0 Junior Debt Market Yield 35.8 11.0 - 25.5 13.2 Other Various 66.4 Total Level 3 Fixed Maturity Investments $ 189.2		The table below presents quantitative information about the significant unobservable inputs utilized by the Company in determining fair values for fixed maturity investments classified as Level 3 at December 31, 2023. Valuations for assets presented in the tables below are primarily based on broker/dealer quotes for which there is a lack of transparency as to inputs used to develop the valuations. The quantitative detail of these unobservable inputs is neither provided nor reasonably available to the Company. The weighted average yield is calculated based on fair value. (Dollars in Millions) Unobservable Input Total Fair Value Range of Unobservable Inputs Weighted-average Yield Investment-grade Market Yield $ 60.0 4.2 % - 15.8 % 8.7 % Non-investment-grade: Senior Debt Market Yield 32.6 9.2 - 36.7 13.5 Junior Debt Market Yield 32.5 11.8 - 22.5 13.8 Other Various 64.4 Total Level 3 Fixed Maturity Investments $ 189.5
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation	Information by security type pertaining to the changes in the fair value of the Company’s investments classified as Level 3 for the three months ended March 31, 2024 is presented below. Fixed Maturities Equity Securities (Dollars in Millions) Corporate States and Political Redeemable Other Mortgage- Preferred Total Balance, Beginning of Year $ 177.1 $ 0.1 $ 7.1 $ 5.2 $ 2.8 $ 192.3 Total (Losses) Gains: Included in Condensed Consolidated Statements of Income (Loss) (0.2) — — — (0.1) (0.3) Included in Other Comprehensive Income 2.3 (0.4) — (0.1) — 1.8 Purchases 13.2 — — — — 13.2 Sales (3.7) — — — — (3.7) Transfers into Level 3 — 1.7 — — — 1.7 Transfers out of Level 3 (8.2) — (4.9) — — (13.1) Balance, End of Period $ 180.5 $ 1.4 $ 2.2 $ 5.1 $ 2.7 $ 191.9 Information by security type pertaining to the changes in the fair value of the Company’s investments classified as Level 3 for the three months ended March 31, 2023 is presented below. Fixed Maturities Equity Securities (Dollars in Millions) Corporate Redeemable Other Mortgage- Preferred Total Balance, Beginning of Year $ 216.0 $ 6.8 $ 5.1 $ 2.1 $ 230.0 Total Gains (Losses): Included in Condensed Consolidated Statements of Income (Loss) 0.4 — — (0.5) (0.1) Included in Other Comprehensive Income 1.5 — 0.2 — 1.7 Purchases 19.4 — — — 19.4 Sales (41.2) — — — (41.2) Transfers into Level 3 — — — 0.4 0.4 Balance, End of Period $ 196.1 $ 6.8 $ 5.3 $ 2.0 $ 210.2
Fair Value, by Balance Sheet Grouping	Presented below are the carrying values and fair value estimates of financial instruments not carried at fair value. March 31, 2024 December 31, 2023 (Dollars in Millions) Carrying Value Fair Value Carrying Value Fair Value Financial Assets: Loans to Policyholders $ 280.5 $ 280.5 $ 281.2 $ 281.2 Short-term Investments 520.7 520.7 520.9 520.9 Mortgage Loans 93.1 93.1 99.8 99.8 Company-Owned Life Insurance 515.7 515.7 513.5 513.5 Equity Securities at Modified Cost 24.7 24.7 32.6 32.6 Financial Liabilities: Long-term Debt $ 1,389.8 $ 1,246.8 $ 1,389.2 $ 1,213.4 Policyholder Obligations 563.2 563.2 557.4 557.4
Investment Holdings, Other than Securities	The following table includes information related to the Company’s investments in certain private equity funds or hedge funds that calculate a net asset value per share: Asset Class Investment Category Includes Mezzanine Debt Funds with investments in junior or subordinated debt and potentially minority equity securities issued by private companies. Senior Debt Funds with investments in senior or first lien debt and potentially minority equity securities typically issued by private companies. Distressed Debt Funds with debt or minority equity investments that are made opportunistically in companies that are in or near default or under financial strain with potential to have an active role in restructuring company. Secondary Transactions Funds that focus on purchasing third party fund interests from investors seeking liquidity within their own portfolio. Hedge Fund Funds that focus primarily on investing in public securities with strategy of generating uncorrelated returns to the public markets. Leveraged Buyout Funds with control equity investments in more mature, positive cash flowing, private companies that are typically purchased with the use of financial leverage. Growth Equity Funds that invest in early or venture stage companies with high growth potential with view towards generating realizations through sale or initial public offering (“IPO”) of company. Real Estate Funds with investments in multi-family housing properties. Other Consists of direct investments of preferred equity or minority common equity investments into private companies structured as limited partnerships or limited liability companies.
Fair Value Disclosure of Asset and Liability Not Measured at Fair Value	The table below shows investments reported at fair value using NAV and their unfunded commitments by asset class as of March 31, 2024 and December 31, 2023. (Dollars in Millions) March 31, 2024 December 31, 2023 Asset Class Fair Value Using NAV Unfunded Commitments Fair Value Using NAV Unfunded Commitments Reported as Equity Method Limited Liability Investments: Mezzanine Debt $ 123.2 $ 42.6 $ 125.4 $ 43.1 Real Estate 42.0 — 41.9 — Senior Debt 19.2 39.5 19.0 39.9 Leveraged Buyout 8.5 0.6 8.6 0.6 Secondary Transactions 6.8 1.6 7.9 1.7 Distressed Debt 6.1 — 7.9 — Growth Equity 0.8 — 1.2 — Hedge Fund 0.1 — 0.1 — Other 8.5 0.2 9.7 — Total Equity Method Limited Liability Investments 215.2 84.5 221.7 85.3 Reported as Other Equity Interests at Fair Value: Mezzanine Debt 127.7 66.3 124.0 67.0 Senior Debt 24.7 10.8 24.8 10.6 Leveraged Buyout 19.7 9.5 19.0 10.0 Distressed Debt 12.9 13.0 12.4 13.0 Growth Equity 6.3 6.5 6.4 6.5 Secondary Transactions 2.7 3.1 2.8 3.1 Hedge Funds — — 1.9 — Real Estate 0.1 0.2 0.1 0.2 Total Reported as Other Equity Interests at Fair Value 194.1 109.4 191.4 110.4 Reported as Equity Securities at Modified Cost: Other 4.6 — 4.8 — Total Reported as Equity Securities at Modified Cost 4.6 — 4.8 — Total Investments in Limited Liability Companies and Limited Partnerships $ 413.9 $ 193.9 $ 417.9 $ 195.7

Variable Interest Entities (Tab

Variable Interest Entities (Tables)	3 Months Ended
Variable Interest Entities (Tables)	Mar. 31, 2024
Equity Method Investments and Joint Ventures [Abstract]
Schedule of Variable Interest Entities	The following table presents information regarding activity in the Company’s Alternative Energy Partnership Investments for the three months ended March 31, 2024 and 2023. Three Months Ended (Dollars in Millions) Mar 31, 2024 Mar 31, 2023 Cash distribution from Investment 0.5 0.5 Income on Investments in Alternative Energy Partnership 0.4 0.7 Income Tax Credits (Recaptures) Recognized — (0.1) Tax Expense Recognized from Alternative Energy Partnership (0.1) (0.2) The following table represents the carrying value of the associated assets and liabilities and the associated maximum loss exposure of the Alternative Energy Partnership Investments as of March 31, 2024 and December 31, 2023. (Dollars in Millions) Mar 31, 2024 Dec 31, 2023 Cash $ 2.7 $ 2.7 Equipment, Net of Depreciation 255.0 256.2 Other Assets 7.5 7.5 Total Unconsolidated Assets 265.2 266.4 Maximum Loss Exposure 17.2 17.3

Deferred Costs, Capitalized, _2

Deferred Costs, Capitalized, Prepaid, and Other Assets (Tables)	3 Months Ended
	Mar. 31, 2024
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Deferred Policy Acquisition Costs	The following table presents the balances and changes in Deferred Policy Acquisition Costs for the Property and Casualty and Life and Health and business for the three months ended March 31, 2024 and 2023: March 31, 2024 March 31, 2023 Property and Casualty Life and Health Total Property and Casualty Life and Health Total Balance, Beginning of Year $ 164.9 $ 426.7 $ 591.6 $ 231.1 $ 404.5 $ 635.6 Capitalizations 120.0 15.8 135.8 149.5 15.4 164.9 Amortization Expense (125.4) (5.3) (130.7) (142.3) (5.6) (147.9) Experience Adjustment — (1.4) (1.4) — (1.1) (1.1) Balance, End of Period $ 159.5 $ 435.8 $ 595.3 $ 238.3 $ 413.2 $ 651.5

Receivables from Policyholder_2

Receivables from Policyholders - Allowance for Expected Credit Losses (Tables)	3 Months Ended
	Mar. 31, 2024
Credit Loss [Abstract]
Premium Receivable, Allowance for Credit Loss	The following tables present the balances of Receivables from Policyholders, net of the allowance for expected credit losses, as of March 31, 2024 and 2023, and a rollforward of changes in the allowance for expected credit losses for the three months ended March 31, 2024 and 2023. Three Months Ended March 31, 2024 (Dollars in Millions) Specialty Life Total Segments Non-Core Operations Total Allowance for Expected Credit Losses Balance, Beginning of Year $ 12.9 $ — $ 12.9 $ 1.0 $ 13.9 Provision for Expected Credit Losses 6.2 0.1 6.3 0.2 6.5 Write-offs of Uncollectible Receivables from Policyholders (13.7) (0.1) (13.8) (0.2) (14.0) Balance, End of Period $ 5.4 $ — $ 5.4 $ 1.0 $ 6.4 Receivable Balance, End of Period $ 892.8 $ 10.5 $ 903.3 $ 49.8 $ 953.1 Three Months Ended March 31, 2023 (Dollars in Millions) Specialty Life Total Segments Non-Core Operations Total Allowance for Expected Credit Losses Balance, Beginning of Year $ 12.3 $ — $ 12.3 $ 0.8 $ 13.1 Provision for Expected Credit Losses 10.3 0.3 10.6 0.4 11.0 Write-offs of Uncollectible Receivables from Policyholders (12.0) (0.3) (12.3) (0.5) (12.8) Balance, End of Period $ 10.6 $ — $ 10.6 $ 0.7 $ 11.3 Receivable Balance, End of Period $ 1,232.7 $ 9.7 $ 1,242.4 $ 101.6 $ 1,344.0

Other Comprehensive Income an_2

Other Comprehensive Income and Accumulated Other Comprehensive Loss (Tables)	3 Months Ended
	Mar. 31, 2024
Statement of Comprehensive Income [Abstract]
Schedule of Comprehensive Income	The tables below display the changes in Accumulated Other Comprehensive Loss by component for the three months ended March 31, 2024 and 2023. (Dollars in Millions) Net Unrealized Losses on Other Investments Net Unrealized Losses on Investments with an Allowance for Credit Losses Net Unrecognized Postretirement Benefit Income Gain on Cash Flow Hedges Change in Discount Rate on Future Life Policyholder Benefits Total Balance as of January 1, 2024 $ (530.9) $ (2.5) $ 9.5 $ 2.5 $ 160.6 (360.8) Other Comprehensive (Loss) Income Before Reclassifications (96.1) 1.6 — — 111.5 17.0 Amounts Reclassified from Accumulated Other Comprehensive Loss Net of Tax (Expense) Benefit of $(2.6), $0.2, $0.1, $0.0, $0.0 and $(2.3) 9.8 (0.2) (0.8) — — 8.8 Other Comprehensive (Loss) Income Net of Tax Benefit (Expense) of $22.7, $0.1, $0.1, $0.0, $(29.6), and $(6.7) (86.3) 1.4 (0.8) — 111.5 25.8 Balance as of March 31, 2024 $ (617.2) $ (1.1) $ 8.7 $ 2.5 $ 272.1 $ (335.0) (Dollars in Millions) Net Unrealized Losses on Other Investments Net Unrealized Losses on Investments with an Allowance for Credit Losses Net Unrecognized Postretirement Benefit Costs Gain (Loss) on Cash Flow Hedges Change in Discount Rate on Future Life Policyholder Benefits Total Balance as of January 1, 2023 $ (719.4) $ (2.2) $ (37.2) $ 2.8 $ 241.1 $ (514.9) Other Comprehensive Income (Loss) Before Reclassifications 147.5 1.4 — — (86.7) 62.2 Amounts Reclassified from Accumulated Other Comprehensive Loss Net of Tax Benefit (Expense) of $0.0, $0.4, $(0.1), $0.1, $0.0 and $0.4 (0.1) (1.4) (0.4) (0.1) — (2.0) Other Comprehensive Income (Loss) Net of Tax (Expense) Benefit of $(39.8), $(0.4), $0.0, $0.0, $23.1, and $(17.1) 147.4 — (0.4) (0.1) (86.7) 60.2 Balance as of March 31, 2023 $ (572.0) $ (2.2) $ (37.6) $ 2.7 $ 154.4 $ (454.7) Amounts reclassified from Accumulated Other Comprehensive Loss shown above are reported in Net Income (Loss) as follows: Components of AOCI Condensed Consolidated Statements of Income (Loss) Line Item Affected by Reclassifications Net Unrealized Losses on Other Investments and Net Unrealized Losses on Investments with an Allowance for Credit Losses Net Realized Investment Gains and Impairment Losses Net Unrecognized Postretirement Benefit Income (Costs) Policyholders’ Benefits and Incurred Losses and Loss Adjustment Expenses, Insurance Expenses, and Interest and Other Expenses Gain (Loss) on Cash Flow Hedges Interest and Other Expenses

Policyholder Contract Liabili_2

Policyholder Contract Liabilities (Tables)	3 Months Ended
Policyholder Contract Liabilities (Tables)	Mar. 31, 2024
Insurance [Abstract]
Schedule of Liability for Future Policy Benefits, by Product Segment	Policyholder Obligations at March 31, 2024 and December 31, 2023 were as follows: (Dollars in Millions) Mar 31, Dec 31, FHLB Funding Agreements $ 563.2 $ 557.4 Universal Life-type Policyholder Account Balances 97.7 98.3 Total $ 660.9 $ 655.7
Schedule of Federal Home Loan Bank, Advances, by Branch of FHLB Bank	United Insurance’s liability under the funding agreements with the FHLB of Chicago, the amount of collateral pledged under such agreements and FHLB of Chicago common stock owned by United Insurance at March 31, 2024 and December 31, 2023 is presented below. (Dollars in Millions) Mar 31, Dec 31, Liability under Funding Agreements $ 563.2 $ 557.4 Fair Value of Collateral Pledged 712.1 629.3 FHLB of Chicago Common Stock Owned at Cost 16.3 16.6

Debt (Tables)

Debt (Tables)	3 Months Ended
Debt (Tables)	Mar. 31, 2024
Debt Disclosure [Abstract]
Schedule of Long-term Debt Instruments	Total amortized cost of Long-term Debt, Current and Non-Current, outstanding at March 31, 2024 and December 31, 2023 was: (Dollars in Millions) Mar 31, Dec 31, Senior Notes: Current: 4.350% Senior Notes due February 15, 2025 $ 449.7 $ — Non-Current: 4.350% Senior Notes due February 15, 2025 — 449.6 2.400% Senior Notes due September 30, 2030 397.1 397.0 3.800% Senior Notes due February 23, 2032 396.1 396.0 5.875% Fixed-Rate Reset Junior Subordinated Debentures due 2062 146.9 146.6 Total Long-term Debt Outstanding $ 1,389.8 $ 1,389.2

Leases (Tables)

Leases (Tables)	3 Months Ended
Leases (Tables)	Mar. 31, 2024
Leases [Abstract]
Lease, Cost	The following table presents operating lease right-of-use assets and lease liabilities. (Dollars in Millions) Mar 31, Dec 31, Operating Lease Right-of-Use Assets $ 36.1 $ 38.4 Operating Lease Liabilities 58.3 62.3 Lease expenses are primarily included in insurance expenses in the Condensed Consolidated Statements of Income (Loss). Additional information regarding the Company’s operating leases is presented below. Three Months Ended (Dollars in Millions) Mar 31, Mar 31, Lease Cost: Operating Lease Cost $ 3.9 $ 4.1 Variable Lease Cost 1.1 0.1 Short-Term Lease Cost 1 — — Total Lease Expense $ 5.0 $ 4.2 Total Lease Cost $ 5.0 $ 4.2 1 Leases with an initial term of twelve months or less are not recorded on the Condensed Consolidated Balance Sheets. Significant judgments and assumptions for determining lease asset and liability at March 31, 2024 and 2023 are presented below. Three Months Ended Mar 31, Mar 31, Weighted-average Remaining Lease Term - Operating Leases 5.5 years 5.6 years Weighted-average Discount Rate - Operating Leases 4.3 % 3.6 %
Lessee, Operating Lease, Liability, to be Paid, Maturity	Future minimum lease payments under operating leases at March 31, 2024 are presented below. (Dollars in Millions) March 31, 2024 Remainder of 2024 $ 15.0 2025 15.7 2026 9.7 2027 7.4 2028 4.7 2029 and Thereafter 15.2 Total Future Payments $ 67.7 Less: Discount 9.4 Present Value of Minimum Lease Payments $ 58.3

Net Income (Loss) Per Unrestr_3

Net Income (Loss) Per Unrestricted Share - Reconciliation of Numerator and Denominator Used in Calculation (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Earnings Per Share [Abstract]
Net Income (Loss)	$ 71.3	$ (80.1)
Weighted-Average Unrestricted Shares Outstanding (in shares)	64,254,500	63,946,600
Equity-based Compensation Equivalent Shares (in shares)	518,300	0
Weighted-Average Unrestricted Shares and Equivalent Shares Outstanding Assuming Dilution (in shares)	64,772,800	63,946,600
Basic (in dollars per share)	$ 1.11	$ (1.25)
Diluted (in dollars per share)	$ 1.10	$ (1.25)

Net Income (Loss) Per Unrestr_4

Net Income (Loss) Per Unrestricted Share - Antidilutive (Details) - shares shares in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Stock Options
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share, amount (in shares)	1.7	2.5

Business Segments - Narrative (

Business Segments - Narrative (Details)	3 Months Ended
Business Segments - Narrative (Details)	Mar. 31, 2024 segments
Segment Reporting [Abstract]
Number of operating segments	2

Business Segments - Earned Prem

Business Segments - Earned Premiums by Product Line (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Segment Reporting Information [Line Items]
Premiums Earned, Net	$ 1,031.9	$ 1,180.9
Operating Segments \| Specialty Property & Casualty Insurance
Segment Reporting Information [Line Items]
Premiums Earned, Net	840	944.2
Operating Segments \| Life Insurance
Segment Reporting Information [Line Items]
Premiums Earned, Net	97.3	99.3
Operating Segments \| Specialty and Life Insurance
Segment Reporting Information [Line Items]
Premiums Earned, Net	937.3	1,043.5
Operating Segments \| Preferred Property & Casualty Insurance
Segment Reporting Information [Line Items]
Premiums Earned, Net	94.6	137.4
Operating Segments \| Personal Automobile \| Specialty Property & Casualty Insurance
Segment Reporting Information [Line Items]
Premiums Earned, Net	675.3	787.9
Operating Segments \| Commercial Automobile \| Specialty Property & Casualty Insurance
Segment Reporting Information [Line Items]
Premiums Earned, Net	164.7	156.3
Operating Segments \| Life \| Life Insurance
Segment Reporting Information [Line Items]
Premiums Earned, Net	80.6	82.2
Operating Segments \| Accident and Health \| Life Insurance
Segment Reporting Information [Line Items]
Premiums Earned, Net	5.6	5.9
Operating Segments \| Property \| Life Insurance
Segment Reporting Information [Line Items]
Premiums Earned, Net	$ 11.1	$ 11.2

Business Segments - Segment Rev

Business Segments - Segment Revenues (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Segment Reporting Information [Line Items]
Premiums Earned, Net	$ 1,031.9	$ 1,180.9
Net Investment Income	100.4	101.8
Change in Value of Alternative Energy Partnership Investments	0.4	0.7
Other Income	1.8	1.2
Total Revenues	1,143	1,294.8
Change in Fair Value of Equity and Convertible Securities	3.4	1.7
Operating Segments
Segment Reporting Information [Line Items]
Total Revenues	1,024.4	1,132.9
Operating Segments \| Specialty Property & Casualty Insurance
Segment Reporting Information [Line Items]
Premiums Earned, Net	840	944.2
Net Investment Income	41.1	38.5
Change in Value of Alternative Energy Partnership Investments	0.3	0.4
Other Income	1.1	0.9
Total Revenues	882.5	984
Operating Segments \| Preferred Property & Casualty Insurance
Segment Reporting Information [Line Items]
Premiums Earned, Net	94.6	137.4
Total Revenues	106.2	148
Operating Segments \| Life Insurance
Segment Reporting Information [Line Items]
Premiums Earned, Net	97.3	99.3
Net Investment Income	44.3	49.8
Change in Value of Alternative Energy Partnership Investments	0.1	0.2
Other Income	0.2	(0.4)
Total Revenues	141.9	148.9
Segment Reconciling Items
Segment Reporting Information [Line Items]
Change in Fair Value of Equity and Convertible Securities	3.4	1.7
Gain (Loss) on Sale of Investments	6.6	6.4
Net Impairment Losses Recognized in Earnings	(1.5)	2.1
Other	$ 3.9	$ 3.7

Business Segments - Segment Ope

Business Segments - Segment Operating Profit (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Segment Reporting Information [Line Items]
Operating Income (Loss)	$ 86.3	$ (72.8)
Corporate and Other Adjusted Operating Loss From:
Less: Net (Loss) Income attributable to Noncontrolling Interest	(1.4)	0
Change in Fair Value of Equity and Convertible Securities	3.4	1.7
Net Realized Investment Gains	6.6	6.4
Income (Loss) before Income Taxes	88	(103.9)
Operating Segments
Segment Reporting Information [Line Items]
Operating Income (Loss)	100.5	(59.9)
Operating Segments \| Specialty Property & Casualty Insurance
Segment Reporting Information [Line Items]
Operating Income (Loss)	86.5	(74.7)
Operating Segments \| Preferred Property & Casualty Insurance
Segment Reporting Information [Line Items]
Operating Income (Loss)	6	(12.2)
Operating Segments \| Life Insurance
Segment Reporting Information [Line Items]
Operating Income (Loss)	14	14.8
Corporate and Other
Segment Reporting Information [Line Items]
Operating Income (Loss)	(15.6)	(12.9)
Segment Reconciling Items
Corporate and Other Adjusted Operating Loss From:
Change in Fair Value of Equity and Convertible Securities	3.4	1.7
Net Realized Investment Gains	6.6	6.4
Impairment Losses	(1.5)	2.1
Acquisition and Disposition Related Transaction, Integration, Restructuring and Other Costs	$ (12.8)	$ (29.1)

Business Segments - Segment Net

Business Segments - Segment Net Operating Income (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Segment Reporting Information [Line Items]
Segment Net Operating Income (Loss)	$ 69.7	$ (55.7)
Less: Net (Loss) Income attributable to Noncontrolling Interest	(1.1)	0
Net Income (Loss)	71.3	(80.1)
Operating Segments
Segment Reporting Information [Line Items]
Segment Net Operating Income (Loss)	81.1	(45.2)
Operating Segments \| Specialty Property & Casualty Insurance
Segment Reporting Information [Line Items]
Segment Net Operating Income (Loss)	69.2	(58.4)
Operating Segments \| Preferred Property & Casualty Insurance
Segment Reporting Information [Line Items]
Segment Net Operating Income (Loss)	5	(9.5)
Operating Segments \| Life Insurance
Segment Reporting Information [Line Items]
Segment Net Operating Income (Loss)	11.9	13.2
Corporate and Other
Segment Reporting Information [Line Items]
Segment Net Operating Income (Loss)	(12.5)	(10.5)
Segment Reconciling Items
Segment Reporting Information [Line Items]
Change in Fair Value of Equity and Convertible Securities	2.7	1.3
Net Realized Investment Gains	5.2	5.1
Other than Temporary Impairment Losses, Investments, Portion Recognized in Earnings, Net of Tax	(1.2)	1.7
Acquisition and Disposition Related Transaction, Integration, Restructuring and Other Costs	$ (10.1)	$ (23)

Property and Casualty Insuran_3

Property and Casualty Insurance Reserves - Reserve Activity (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Incurred Losses and LAE related to:
Incurred Losses and LAE Related to Prior Years	$ 8.8	$ 41.9
Property, Liability and Casualty Insurance Product Line
Liability for Unpaid Claims and Claims Adjustment Expense [Roll Forward]
Gross of Reinsurance at Beginning of Year	2,680.5	2,756.9
Less Reinsurance Recoverables at Beginning of Year	27.8	39.6
Property and Casualty Insurance Reserves, Net of Reinsurance at Beginning of Year	2,652.7	2,717.3
Incurred Losses and LAE related to:
Incurred Losses and LAE Related to Current Year	686.1	944
Incurred Losses and LAE Related to Prior Years	8.8	41.9
Total Incurred Losses and LAE	694.9	985.9
Paid Losses and LAE related to:
Paid Losses and LAE Related to Current Year	213.9	325.5
Paid Losses and LAE Related to Prior Years	562.9	690.9
Total Paid Losses and LAE	776.8	1,016.4
Property and Casualty Insurance Reserves, Net of Reinsurance at End of Period	2,570.8	2,686.8
Plus Reinsurance Recoverables at End of Period	26.4	34.3
Property and Casualty Insurance Reserves, Gross of Reinsurance at End of Period	$ 2,597.2	$ 2,721.1

Property and Casualty Insuran_4

Property and Casualty Insurance Reserves - Narrative (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred Losses and LAE Related to Prior Years	$ 8.8	$ 41.9
Personal Automobile
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred Losses and LAE Related to Prior Years	7.1	22.9
Preferred Automobile [Member]
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred Losses and LAE Related to Prior Years	(2.9)	3.4
Homeowners [Member]
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred Losses and LAE Related to Prior Years	3.6	5.5
Other Personal Lines [Member]
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred Losses and LAE Related to Prior Years	2.2	1.9
Commercial Automobile
Liability for Claims and Claims Adjustment Expense [Line Items]
Incurred Losses and LAE Related to Prior Years	$ (1.1)	$ 8.2

Liability for Future Policyho_3

Liability for Future Policyholder Benefits - Changes in Premiums, Discounts and Benefits (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023	Dec. 31, 2022
Liability for Future Policy Benefit, by Product Segment [Line Items]
Liability for Future Policy Benefit, Weighted-Average Duration	14 years 7 months 6 days		14 years 10 months 24 days
Accounting Standards Update 2018-12
Liability for Future Policy Benefit, by Product Segment [Line Items]
Liability for Future Policy Benefit, Expected Net Premium, before Reinsurance, after Discount Rate Change	$ 690.1	$ 722.4
Liability for Future Policy Benefit, Expected Net Premium, Original Discount Rate, before Cash Flow and Reinsurance	723.1	744.5
Liability for Future Policy Benefit, Expected Net Premium, Original Discount Rate, before Reinsurance, after Cash Flow Change			$ 700	$ 729.6
Present Value of Expected Future Policyholder benefits	3,488.2	3,699.5
Liability for Future Policy Benefit, Expected Future Policy Benefit, Original Discount Rate, before Cash Flow and Reinsurance	3,865.7	3,916.9
Liability for Future Policy Benefit, Expected Future Benefit, Original Discount Rate, before Reinsurance, after Cash Flow Change			3,841.4	3,906.5
Liability for Future Policy Benefit, after Reinsurance	2,798.1	2,977.1
Term Life Insurance
Liability for Future Policy Benefit, by Product Segment [Line Items]
Net Liability for Future Policyholder Benefits	10,225.9	10,177.7
Term Life Insurance \| Accounting Standards Update 2018-12
Liability for Future Policy Benefit, by Product Segment [Line Items]
Liability for Future Policy Benefit, Expected Net Premium, before Reinsurance, after Discount Rate Change			675.4	688.6
Liability for Future Policy Benefit, Expected Net Premium, Original Discount Rate, before Cash Flow and Reinsurance			694.7	728.9
Liability for Future Policy Benefit, Expected Net Premium, Cumulative Increase (Decrease) from Cash Flow Change	0	0
Liability for Future Policy Benefit, Expected Net Premium, Cumulative Increase (Decrease) of Actual Variance from Expected Experience			5.3	0.7
Liability for Future Policy Benefit, Expected Net Premium, Issuance	38.2	31.8
Liability for Future Policy Benefit, Expected Net Premium, Interest Income	7.6	7
Liability for Future Policy Benefit, Expected Net Premium, Net Premium Collected	(22.7)	(23.9)
AOCI, Liability for Future Policy Benefit, Expected Net Premium, before Tax	(33)	(22.1)
Present Value of Expected Future Policyholder benefits			3,613.2	3,561
Liability for Future Policy Benefit, Expected Future Policy Benefit, Original Discount Rate, before Cash Flow and Reinsurance			3,835.9	3,906.2
Liability for Future Policy Benefit, Expected Future Policy Benefit, Cumulative Increase (Decrease) from Cash Flow Change	0	0
Liability for Future Policy Benefit, Expected Future Policy Benefit, Cumulative Increase (Decrease) of Actual Variance from Expected Experience			$ 5.5	$ 0.3
Liability for Future Policy Benefit, Expected Future Policy Benefit, Issuance	38.2	31.8
Liability for Future Policy Benefit, Expected Future Policy Benefit, Interest Expense	42.6	42.4
Liability for Future Policy Benefit, Expected Future Policy Benefit, Benefit Payment	(56.5)	(63.8)
AOCI, Liability for Future Policy Benefit, Expected Future Policy Benefit, before Tax	(377.5)	(217.4)
Net Liability for Future Policyholder Benefits	2,798.1	2,977.1
Liability for Future Policy Benefit, Reinsurance Recoverable, after Allowance	$ 0	$ 0

Liability for Future Policyho_4

Liability for Future Policyholder Benefits - Reconciliation of the Net Liability for Future Benefits to Life and Health Insurance Reserves (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023	Dec. 31, 2022
Insurance [Abstract]
Net Liability for Future Policyholder Benefits	$ 2,798,100	$ 2,977,100
Deferred Profit Liability	357,500	272,600	$ 337,800	$ 253,600
A&H and Other Reserves	138,700	149,900
Total Life and Health Insurance Reserves	3,294,300	3,399,600
Liability for Future Policy Benefit, by Product Segment [Line Items]
Net Liability for Future Policyholder Benefits	2,798,100	2,977,100
Deferred Profit Liability	357,500	272,600	$ 337,800	$ 253,600
A&H and Other Reserves	138,700	149,900
Total Life and Health Insurance Reserves	3,294,300	3,399,600
Term Life Insurance
Insurance [Abstract]
Gross Premiums or Assessments	101,300	103,800
Interest Expense	35,000	35,400
Liability for Future Policy Benefit, by Product Segment [Line Items]
Net Liability for Future Policyholder Benefits	10,225,900	10,177,700
Liability for Future Policy Benefit, Expected Future Gross Premium, Undiscounted, before Reinsurance	4,136,000	4,464,200
Liability for Future Policy Benefit, Expected Future Gross Premium, Discounted, before Reinsurance	2,758,300	2,931,100
Gross Premiums or Assessments	101,300	103,800
Interest Expense	$ 35,000	$ 35,400
Liability for Future Policy Benefit, Weighted-Average Interest Accretion Rate	4.55%	4.55%
Liability for Future Policy Benefit, Current Weighted-Average Discount Rate	5.40%	5.05%

Liability for Future Policyho_5

Liability for Future Policyholder Benefits - Changes in Deferred Profit Liability (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Deferred Profit Liability [Roll Forward]
Balance, beginning of period	$ 337.8	$ 253.6
Profits deferred	41.8	43
Interest accrual	4	3
Amortization	(25.9)	(27)
Effect of actual variances from expected experience and other changes	(0.2)	0
Balance, end of period	$ 357.5	$ 272.6

Investments - Schedule of Fixed

Investments - Schedule of Fixed Maturities (Details) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023	Mar. 31, 2023	Dec. 31, 2022
Debt Securities, Available-for-sale [Line Items]
Fixed maturities, at amortized cost	$ 7,562.1
Gross unrealized gains	25.3
Gross unrealized loss	(808.1)
Fixed maturities, allowance for credit losses	(7.7)	$ (8.2)	$ 7.4	$ 9.6
Fixed maturities at fair value	6,771.6
Investments in Fixed Maturities
Debt Securities, Available-for-sale [Line Items]
Fixed maturities, at amortized cost		7,565.8
Gross unrealized gains		54.6
Gross unrealized loss		(730.3)
Fixed maturities at fair value		6,881.9
Debt securities, available-for-sale, unrealized loss position, accumulated loss	808.1	730.3
Investments in Fixed Maturities \| External Credit Rating, Investment Grade [Member]
Debt Securities, Available-for-sale [Line Items]
Debt securities, available-for-sale, unrealized loss position, accumulated loss	788.7	704.8
U.S. Government and Government Agencies and Authorities
Debt Securities, Available-for-sale [Line Items]
Fixed maturities, at amortized cost	582.3	594.1
Gross unrealized gains	1	1.9
Gross unrealized loss	(94.9)	(84.5)
Fixed maturities, allowance for credit losses	0	0
Fixed maturities at fair value	488.4	511.5
Debt securities, available-for-sale, unrealized loss position, accumulated loss	94.9	84.5
States and Political Subdivisions
Debt Securities, Available-for-sale [Line Items]
Fixed maturities, at amortized cost	1,552.3	1,575.9
Gross unrealized gains	9.9	16.3
Gross unrealized loss	(205.8)	(189.8)
Fixed maturities, allowance for credit losses	(0.5)	(0.5)
Fixed maturities at fair value	1,355.9	1,401.9
Debt securities, available-for-sale, unrealized loss position, accumulated loss	205.8	189.8
Foreign Governments
Debt Securities, Available-for-sale [Line Items]
Fixed maturities, at amortized cost	5.2	4.4
Gross unrealized gains	0	0
Gross unrealized loss	(0.6)	(0.6)
Fixed maturities, allowance for credit losses	0	0	0.8	0.7
Fixed maturities at fair value	4.6	3.8
Debt securities, available-for-sale, unrealized loss position, accumulated loss	0.6	0.6
Corporate Debt Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Fixed maturities, at amortized cost	4,077.8	4,046.8
Gross unrealized gains	13	35.5
Gross unrealized loss	(448)	(383.8)
Fixed maturities, allowance for credit losses	(7.2)	(7.7)	6.6	$ 8.9
Fixed maturities at fair value	3,635.6	3,690.8
Debt securities, available-for-sale, unrealized loss position, accumulated loss	448	383.8
Mandatorily Redeemable Preferred Stock [Member]
Debt Securities, Available-for-sale [Line Items]
Fixed maturities, at amortized cost	9	9
Gross unrealized gains	0.1	0.1
Gross unrealized loss	(1.1)	(0.8)
Fixed maturities, allowance for credit losses	0	0
Fixed maturities at fair value	8	8.3
Debt securities, available-for-sale, unrealized loss position, accumulated loss	1.1		$ 0.8
Collateralized Loan Obligations
Debt Securities, Available-for-sale [Line Items]
Fixed maturities, at amortized cost	952.5	973.6
Gross unrealized gains	1.1	0.7
Gross unrealized loss	(15.4)	(24.5)
Fixed maturities, allowance for credit losses	0	0
Fixed maturities at fair value	938.2	949.8
Debt securities, available-for-sale, unrealized loss position, accumulated loss	15.4	24.5
Other Mortgage- and Asset-backed
Debt Securities, Available-for-sale [Line Items]
Fixed maturities, at amortized cost	383	362
Gross unrealized gains	0.2	0.1
Gross unrealized loss	(42.3)	(46.3)
Fixed maturities, allowance for credit losses	0	0
Fixed maturities at fair value	340.9	315.8
Debt securities, available-for-sale, unrealized loss position, accumulated loss	$ 42.3	$ 46.3

Investments - Narrative (Detail

Investments - Narrative (Details) - USD ($) $ in Millions	3 Months Ended
Investments - Narrative (Details) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023	Mar. 31, 2023	Dec. 31, 2022
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-Sale, Maturity, without Single Maturity Date, Fair Value	$ 1,664.2
Financing Receivable, Accrued Interest, before Allowance for Credit Loss	74.8	$ 77
Fixed maturities, allowance for credit losses	(7.7)	(8.2)	$ 7.4	$ 9.6
Equity securities without readily determinable fair value, impairment loss, cumulative amount	$ 7.1
Percentage of Equity Method Limited Liability Investments reported with a lag	2.90%
Percentage of Equity Method Limited Liability Investments reported with a One Month Lag	4.80%
Company-Owned Life Insurance	$ 515.7	513.5
Loans to Policyholders	280.5
Loans to Policyholders		281.2
Equity Securities
Debt Securities, Available-for-sale [Line Items]
Other than Temporary Impairment Losses, Investments	0.4
Government National Mortgage Association Certificates and Obligations (GNMA)
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-Sale, Maturity, without Single Maturity Date, Fair Value	227.4
Federal National Mortgage Association Certificates and Obligations (FNMA)
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-Sale, Maturity, without Single Maturity Date, Fair Value	95.3
Federal Home Loan Mortgage Corporation Certificates and Obligations (FHLMC)
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-Sale, Maturity, without Single Maturity Date, Fair Value	62.5
Other Non-Governmental Issuers
Debt Securities, Available-for-sale [Line Items]
Debt Securities, Available-for-Sale, Maturity, without Single Maturity Date, Fair Value	1,279.1
Investments in Fixed Maturities
Debt Securities, Available-for-sale [Line Items]
Debt securities, available-for-sale, unrealized loss position, accumulated loss	808.1	730.3
12 Months or Longer	790.8	721.2
Other Receivables	6	0.9
Other liabilities	21.7	0
Equity Securities
Debt Securities, Available-for-sale [Line Items]
Other Receivables	0.1	0.1
Equity Securities \| Fair Value, Measurements, Recurring
Debt Securities, Available-for-sale [Line Items]
Equity securities	230.1	225.8
Equity Securities, FV-NI, Current	230.1	225.8
Equity Securities \| Fair Value, Inputs, Level 1 [Member] \| Fair Value, Measurements, Recurring
Debt Securities, Available-for-sale [Line Items]
Equity securities	9.6	8.5
Equity Securities, FV-NI, Current	9.6	8.5
Preferred Stocks \| All Industries Other than Finance, Insurance and Real Estate [Member] \| Fair Value, Measurements, Recurring
Debt Securities, Available-for-sale [Line Items]
Equity securities	10	9.9
Equity Securities, FV-NI, Current	10	9.9
Preferred Stocks \| All Industries Other than Finance, Insurance and Real Estate [Member] \| Fair Value, Inputs, Level 1 [Member] \| Fair Value, Measurements, Recurring
Debt Securities, Available-for-sale [Line Items]
Equity securities	0	0
Equity Securities, FV-NI, Current	0	0
Common Stock [Member] \| All Industries Other than Finance, Insurance and Real Estate [Member] \| Fair Value, Measurements, Recurring
Debt Securities, Available-for-sale [Line Items]
Equity securities	0.8	0.6
Equity Securities, FV-NI, Current	0.8	0.6
Common Stock [Member] \| All Industries Other than Finance, Insurance and Real Estate [Member] \| Fair Value, Inputs, Level 1 [Member] \| Fair Value, Measurements, Recurring
Debt Securities, Available-for-sale [Line Items]
Equity securities	0.3	0.2
Equity Securities, FV-NI, Current	0.3	0.2
Corporate Debt Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Debt securities, available-for-sale, unrealized loss position, accumulated loss	448	383.8
12 Months or Longer	436.5	378.3
Fixed maturities, allowance for credit losses	(7.2)	(7.7)	$ 6.6	$ 8.9
Equity Method Investments
Debt Securities, Available-for-sale [Line Items]
Other liabilities	0	0
Variable Interest Entity, Not Primary Beneficiary
Debt Securities, Available-for-sale [Line Items]
Variable Interest Entity, Reporting Entity Involvement, Maximum Loss Exposure, Amount	17.2	17.3
Variable Interest Entity, Not Primary Beneficiary \| Equity Method Limited Liability Investments
Debt Securities, Available-for-sale [Line Items]
Outstanding commitments to fund equity method limited liability investments	84.5
External Credit Rating, Investment Grade [Member] \| Investments in Fixed Maturities
Debt Securities, Available-for-sale [Line Items]
Debt securities, available-for-sale, unrealized loss position, accumulated loss	788.7	704.8
Non-investment-grade \| Investments in Fixed Maturities
Debt Securities, Available-for-sale [Line Items]
Debt securities, available-for-sale, unrealized loss position, accumulated loss	$ 19.4	$ 25.5
Percentage of unrealized loss position to amortized cost basis of available for sale security average	6.40%	8.80%

Investments - Amortized Costs a

Investments - Amortized Costs and Estimated Fair Value (Details) $ in Millions	Mar. 31, 2024 USD ($)
Amortized Cost
Due in One Year or Less	$ 195.2
Debt Securities, Available-for-Sale, Maturity, Allocated and Single Maturity Date, Rolling after One Through Five Years, Amortized Cost	896.7
Debt Securities, Available-for-Sale, Maturity, Allocated and Single Maturity Date, Rolling after 5 through 10 Years, Amortized Cost	1,062.2
Debt Securities, Available-for-Sale, Maturity, Allocated and Single Maturity Date, Rolling after 10 Years, Amortized Cost	3,604.5
Debt Securities, Available-for-Sale, Maturity, without Single Maturity Date, Amortized Cost	1,803.5
Fixed maturities, at amortized cost	7,562.1
Fair Value
Debt Securities, Available-for-Sale, Maturity, Allocated and Single Maturity Date, Rolling within One Year, Fair Value	190.8
Debt Securities, Available-for-Sale, Maturity, Allocated and Single Maturity Date, Rolling after One Through Five Years, Fair Value	867.5
Debt Securities, Available-for-Sale, Maturity, Allocated and Single Maturity Date, Rolling after 5 through 10 Years, Fair Value	924.1
Debt Securities, Available-for-Sale, Maturity, Allocated and Single Maturity Date, Rolling after 10 Years, Fair Value	3,125
Debt Securities, Available-for-Sale, Maturity, without Single Maturity Date, Fair Value	1,664.2
Debt Securities, Available-for-Sale	$ 6,771.6

Investments - Continuous Unreal

Investments - Continuous Unrealized Loss (Details) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023	Mar. 31, 2023
U.S. Government and Government Agencies and Authorities
Fixed Maturities:
Fair Value	$ 46.5	$ 52
Fair Value	393	401.6
Fair Value	439.5	453.6
Fixed Maturities:
Unrealized Losses	(1.6)	(0.8)
Unrealized Losses	(93.3)	(83.7)
Unrealized Losses	(94.9)	(84.5)
States and Political Subdivisions
Fixed Maturities:
Fair Value	165	112.9
Fair Value	962	928.3
Fair Value	1,127	1,041.2
Fixed Maturities:
Unrealized Losses	(3.3)	(2.3)
Unrealized Losses	(202.5)	(187.5)
Unrealized Losses	(205.8)	(189.8)
Foreign Governments
Fixed Maturities:
Fair Value	0.9	0
Fair Value	1.7	1.9
Fair Value	2.6	1.9
Fixed Maturities:
Unrealized Losses	0	0
Unrealized Losses	(0.6)	(0.6)
Unrealized Losses	(0.6)	(0.6)
Corporate Debt Securities [Member]
Fixed Maturities:
Fair Value	432.3	198.4
Fair Value	2,801.7	2,813
Fair Value	3,234	3,011.4
Fixed Maturities:
Unrealized Losses	(11.5)	(5.5)
Unrealized Losses	(436.5)	(378.3)
Unrealized Losses	(448)	(383.8)
Mandatorily Redeemable Preferred Stock [Member]
Fixed Maturities:
Fair Value	0		$ 0
Fair Value	7.6		7.9
Fair Value	7.6		7.9
Fixed Maturities:
Unrealized Losses	0		0
Unrealized Losses	(1.1)		(0.8)
Unrealized Losses	(1.1)		$ (0.8)
Collateralized Loan Obligations
Fixed Maturities:
Fair Value	231.6	38.8
Fair Value	246.7	747.7
Fair Value	478.3	786.5
Fixed Maturities:
Unrealized Losses	(0.8)	(0.4)
Unrealized Losses	(14.6)	(24.1)
Unrealized Losses	(15.4)	(24.5)
Other Mortgage- and Asset-backed
Fixed Maturities:
Fair Value	14.9	15.7
Fair Value	292.5	287.3
Fair Value	307.4	303
Fixed Maturities:
Unrealized Losses	(0.1)	(0.1)
Unrealized Losses	(42.2)	(46.2)
Unrealized Losses	(42.3)	(46.3)
Investments in Fixed Maturities
Fixed Maturities:
Fair Value	891.2	417.8
Fair Value	4,705.2	5,187.7
Fair Value	5,596.4	5,605.5
Fixed Maturities:
Unrealized Losses	(17.3)	(9.1)
Unrealized Losses	(790.8)	(721.2)
Unrealized Losses	(808.1)	(730.3)
Investments in Fixed Maturities \| Non-investment-grade
Fixed Maturities:
Unrealized Losses	$ (19.4)	$ (25.5)

Investments - Allowance for Cre

Investments - Allowance for Credit Losses (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Debt Securities, Available-for-sale, Allowance for Credit Loss [Roll Forward]
Balance, Beginning of Year	$ (8.2)	$ 9.6
Additions for Securities for which No Previous Expected Credit Losses were Recognized		(0.3)
Reductions Due to Sales	(0.2)	(1.9)
Net Decrease in Allowance on Securities for which Expected Credit Losses were Previously Recognized	(0.3)	0.6
Debt Securities, Available-for-Sale, Allowance for Credit Loss	(7.7)	7.4
Equity securities, FV-NI, unrealized gain (loss)	3.9	4.4
Foreign Governments
Debt Securities, Available-for-sale, Allowance for Credit Loss [Roll Forward]
Balance, Beginning of Year	0	0.7
Additions for Securities for which No Previous Expected Credit Losses were Recognized		0
Net Decrease in Allowance on Securities for which Expected Credit Losses were Previously Recognized		(0.1)
Debt Securities, Available-for-Sale, Allowance for Credit Loss	0	0.8
Corporate Debt Securities [Member]
Debt Securities, Available-for-sale, Allowance for Credit Loss [Roll Forward]
Balance, Beginning of Year	(7.7)	8.9
Additions for Securities for which No Previous Expected Credit Losses were Recognized		(0.3)
Reductions Due to Sales	(0.2)	(1.9)
Net Decrease in Allowance on Securities for which Expected Credit Losses were Previously Recognized	(0.3)	0.7
Debt Securities, Available-for-Sale, Allowance for Credit Loss	(7.2)	6.6
States and Political Subdivisions
Debt Securities, Available-for-sale, Allowance for Credit Loss [Roll Forward]
Balance, Beginning of Year	(0.5)
Reductions Due to Sales	0	$ 0
Net Decrease in Allowance on Securities for which Expected Credit Losses were Previously Recognized	0
Debt Securities, Available-for-Sale, Allowance for Credit Loss	$ (0.5)

Investments - Schedule of Other

Investments - Schedule of Other Investments (Details) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Investments, Debt and Equity Securities [Abstract]
Real Estate at Depreciated Cost	$ 93.9	$ 94.7
Mortgage Loans on Real Estate, Commercial and Consumer, Net	93.1	99.8
Investments and Other Noncurrent Assets	1.9	14.8
Total	213.6	241.9
Equity Securities at Modified Cost	$ 24.7	$ 32.6

Investments - Net Investment In

Investments - Net Investment Income (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Net Investment Income [Line Items]
Investment income (loss)	$ 108.3	$ 108.1
Investment expenses	7.9	6.3
Net Investment Income	100.4	101.8
Fixed Maturities
Net Investment Income [Line Items]
Investment income (loss)	79.8	81.5
Equity Securities
Net Investment Income [Line Items]
Investment income (loss)	2.8	1
Total Alternative Investments
Net Investment Income [Line Items]
Investment income (loss)	1.3	3.7
Equity Method Limited Liability Investments
Net Investment Income [Line Items]
Investment income (loss)	(2.1)	1.1
Limited Liability Investments Included in Equity Securities
Net Investment Income [Line Items]
Investment income (loss)	3.4	2.6
Short-term Investments
Net Investment Income [Line Items]
Investment income (loss)	7.3	2.3
Loans to Policyholders
Net Investment Income [Line Items]
Investment income (loss)	5.2	5.4
Real Estate
Net Investment Income [Line Items]
Investment income (loss)	2.3	2.4
Investment expenses	2.2	2.1
Other Investment Expenses1,2
Net Investment Income [Line Items]
Investment expenses	5.7	4.2
Interest Expense, Other Short-Term Borrowings	5.2	4.7
Universal Life-type Policyholder Account Balances
Net Investment Income [Line Items]
Investment income (loss)	2.5	3
Cash Surrender Value
Net Investment Income [Line Items]
Investment income (loss)	$ 7.1	$ 8.8

Investments - Net Realized Gain

Investments - Net Realized Gains on Sales of Investments (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Fixed Maturities
Net Investment Income [Line Items]
Gains on Sales	$ 12.8	$ 1.1
Losses on Sales	(2.3)	(3.3)
Derivative
Net Investment Income [Line Items]
Gain (Loss) on Hedging Activity	$ (7.9)	$ 8.4

Derivatives - Gross Notional Am

Derivatives - Gross Notional Amount and Estimated Fair Value of Derivatives (Details) - Interest Swap Lock - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Designated as Hedging Instrument
Derivative [Line Items]
Derivative, Notional Amount	$ 74.9	$ 0
Derivative Asset	1.2	0
Estimated fair value, liabilities	0	0
Not Designated as Hedging Instrument
Derivative [Line Items]
Derivative, Notional Amount	0	149.7
Derivative Asset	0	14.7
Estimated fair value, liabilities	$ 0	$ 0

Derivatives - Cash Flow Hedges

Derivatives - Cash Flow Hedges Included in Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Beginning of Year	$ 0	$ (0.4)
Gains (Losses) Deferred in AOCI	1.5	(0.4)
Net Change in AOCI with Current Period Hedging Transactions	(1.3)	0
Gains (Losses) Reclassified into Income	0	(0.5)
Net Comprehensive Gains (Losses) from Cash Flow Hedges	$ 0.2	$ (1.3)

Fair Value Measurements - Fair

Fair Value Measurements - Fair Value Inputs (Details) - USD ($)	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023	Dec. 31, 2022
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases	$ 13,200,000	$ 19,400,000
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Transfers Into Level 3	1,700,000	400,000
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	191,900,000	210,200,000	$ 192,300,000	$ 230,000,000
Included in Condensed Consolidated Statement of Operations	(300,000)	(100,000)
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3	(13,100,000)
Included in Other Comprehensive Income (Loss)	1,800,000	1,700,000
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales	(3,700,000)	(41,200,000)
Fair Value, Equity Securities FV-NI, Entities That Calculate Net Asset Value Per Share, Unfunded Commitments	0		0
Fair Value, Equity Method Investments, Entities That Calculate Net Asset Value Per Share, Unfunded Commitments	84,500,000		85,300,000
Other Funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Equity Method Investments, Entities That Calculate Net Asset Value Per Share, Unfunded Commitments	200,000		0
Equity Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases	0	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Transfers Into Level 3	0	400,000
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	2,700,000	2,000,000	2,800,000	2,100,000
Included in Condensed Consolidated Statement of Operations	(100,000)	(500,000)
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3	0
Included in Other Comprehensive Income (Loss)	0	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales	0	0
States and Political Subdivisions
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Transfers Into Level 3	1,700,000
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	1,400,000		100,000
Included in Condensed Consolidated Statement of Operations	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3	0
Included in Other Comprehensive Income (Loss)	(400,000)
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales	0
Mandatorily Redeemable Preferred Stock [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases	0	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Transfers Into Level 3	0	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	2,200,000	6,800,000	7,100,000	$ 6,800,000
Included in Condensed Consolidated Statement of Operations	0	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3	(4,900,000)
Included in Other Comprehensive Income (Loss)	0	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales	0	$ 0
Fair Value Measured at Net Asset Value Per Share
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, Fair Value Disclosure	413,900,000		417,900,000
Fair Value, Alternative Investments, Entities That Calculate Net Asset Value Per Share, Unfunded Commitments	109,400,000		110,400,000
Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, Fair Value Disclosure	7,002,900,000		7,122,400,000
Derivative Asset			14,700,000
Fair Value, Measurements, Recurring \| Investments in Fixed Maturities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities at fair value	6,771,600,000		6,881,900,000
Fair Value, Measurements, Recurring \| U.S. Government and Government Agencies and Authorities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities at fair value	488,400,000		511,500,000
Fair Value, Measurements, Recurring \| States and Political Subdivisions
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities at fair value	1,355,900,000		1,401,900,000
Fair Value, Measurements, Recurring \| Foreign Governments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities at fair value	4,600,000		3,800,000
Fair Value, Measurements, Recurring \| Corporate Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities at fair value	3,635,600,000		3,690,800,000
Fair Value, Measurements, Recurring \| Redeemable Preferred Stocks
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities at fair value	8,000,000		8,300,000
Fair Value, Measurements, Recurring \| Collateralized Loan Obligations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities at fair value	938,200,000		949,800,000
Fair Value, Measurements, Recurring \| Other Mortgage- and Asset-backed
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities at fair value	340,900,000		315,800,000
Fair Value, Measurements, Recurring \| Equity Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	230,100,000		225,800,000
Fair Value, Measurements, Recurring \| Exchange Traded Funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	8,700,000		7,700,000
Fair Value, Measurements, Recurring \| Partnership Interest [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	194,100,000		191,400,000
Fair Value, Measurements, Recurring \| Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, Fair Value Disclosure	95,000,000		107,300,000
Derivative Asset			0
Fair Value, Measurements, Recurring \| Fair Value, Inputs, Level 1 [Member] \| Investments in Fixed Maturities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities at fair value	85,400,000		98,800,000
Fair Value, Measurements, Recurring \| Fair Value, Inputs, Level 1 [Member] \| U.S. Government and Government Agencies and Authorities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities at fair value	85,400,000		98,800,000
Fair Value, Measurements, Recurring \| Fair Value, Inputs, Level 1 [Member] \| States and Political Subdivisions
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities at fair value	0		0
Fair Value, Measurements, Recurring \| Fair Value, Inputs, Level 1 [Member] \| Foreign Governments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities at fair value	0		0
Fair Value, Measurements, Recurring \| Fair Value, Inputs, Level 1 [Member] \| Corporate Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities at fair value	0		0
Fair Value, Measurements, Recurring \| Fair Value, Inputs, Level 1 [Member] \| Redeemable Preferred Stocks
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities at fair value	0
Fair Value, Measurements, Recurring \| Fair Value, Inputs, Level 1 [Member] \| Mandatorily Redeemable Preferred Stock [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities at fair value			0
Fair Value, Measurements, Recurring \| Fair Value, Inputs, Level 1 [Member] \| Collateralized Loan Obligations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities at fair value	0		0
Fair Value, Measurements, Recurring \| Fair Value, Inputs, Level 1 [Member] \| Other Mortgage- and Asset-backed
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities at fair value	0		0
Fair Value, Measurements, Recurring \| Fair Value, Inputs, Level 1 [Member] \| Equity Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	9,600,000		8,500,000
Fair Value, Measurements, Recurring \| Fair Value, Inputs, Level 1 [Member] \| Exchange Traded Funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	8,700,000		7,700,000
Fair Value, Measurements, Recurring \| Fair Value, Inputs, Level 1 [Member] \| Partnership Interest [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	0		0
Fair Value, Measurements, Recurring \| Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, Fair Value Disclosure	6,521,900,000		6,631,400,000
Derivative Asset			14,700,000
Fair Value, Measurements, Recurring \| Fair Value, Inputs, Level 2 [Member] \| Investments in Fixed Maturities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities at fair value	6,497,000,000		6,593,600,000
Fair Value, Measurements, Recurring \| Fair Value, Inputs, Level 2 [Member] \| U.S. Government and Government Agencies and Authorities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities at fair value	403,000,000		412,700,000
Fair Value, Measurements, Recurring \| Fair Value, Inputs, Level 2 [Member] \| States and Political Subdivisions
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities at fair value	1,354,500,000		1,401,800,000
Fair Value, Measurements, Recurring \| Fair Value, Inputs, Level 2 [Member] \| Foreign Governments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities at fair value	4,600,000		3,800,000
Fair Value, Measurements, Recurring \| Fair Value, Inputs, Level 2 [Member] \| Corporate Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities at fair value	3,455,100,000		3,513,700,000
Fair Value, Measurements, Recurring \| Fair Value, Inputs, Level 2 [Member] \| Redeemable Preferred Stocks
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities at fair value	5,800,000
Fair Value, Measurements, Recurring \| Fair Value, Inputs, Level 2 [Member] \| Mandatorily Redeemable Preferred Stock [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities at fair value			1,200,000
Fair Value, Measurements, Recurring \| Fair Value, Inputs, Level 2 [Member] \| Collateralized Loan Obligations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities at fair value	938,200,000		949,800,000
Fair Value, Measurements, Recurring \| Fair Value, Inputs, Level 2 [Member] \| Other Mortgage- and Asset-backed
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities at fair value	335,800,000		310,600,000
Fair Value, Measurements, Recurring \| Fair Value, Inputs, Level 2 [Member] \| Equity Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	23,700,000		23,100,000
Fair Value, Measurements, Recurring \| Fair Value, Inputs, Level 2 [Member] \| Exchange Traded Funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	0		0
Fair Value, Measurements, Recurring \| Fair Value, Inputs, Level 2 [Member] \| Partnership Interest [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	0		0
Fair Value, Measurements, Recurring \| Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, Fair Value Disclosure	191,900,000		192,300,000
Derivative Asset			0
Fair Value, Measurements, Recurring \| Fair Value, Inputs, Level 3 [Member] \| Investments in Fixed Maturities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities at fair value	189,200,000		189,500,000
Fair Value, Measurements, Recurring \| Fair Value, Inputs, Level 3 [Member] \| U.S. Government and Government Agencies and Authorities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities at fair value	0		0
Fair Value, Measurements, Recurring \| Fair Value, Inputs, Level 3 [Member] \| States and Political Subdivisions
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities at fair value	1,400,000		100,000
Fair Value, Measurements, Recurring \| Fair Value, Inputs, Level 3 [Member] \| Foreign Governments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities at fair value	0		0
Fair Value, Measurements, Recurring \| Fair Value, Inputs, Level 3 [Member] \| Corporate Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities at fair value	180,500,000		177,100,000
Fair Value, Measurements, Recurring \| Fair Value, Inputs, Level 3 [Member] \| Redeemable Preferred Stocks
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities at fair value	2,200,000
Fair Value, Measurements, Recurring \| Fair Value, Inputs, Level 3 [Member] \| Mandatorily Redeemable Preferred Stock [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities at fair value			7,100,000
Fair Value, Measurements, Recurring \| Fair Value, Inputs, Level 3 [Member] \| Collateralized Loan Obligations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities at fair value	0		0
Fair Value, Measurements, Recurring \| Fair Value, Inputs, Level 3 [Member] \| Other Mortgage- and Asset-backed
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities at fair value	5,100,000		5,200,000
Fair Value, Measurements, Recurring \| Fair Value, Inputs, Level 3 [Member] \| Equity Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	2,700,000		2,800,000
Fair Value, Measurements, Recurring \| Fair Value, Inputs, Level 3 [Member] \| Exchange Traded Funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	0		0
Fair Value, Measurements, Recurring \| Fair Value, Inputs, Level 3 [Member] \| Partnership Interest [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	0		0
Finance, Insurance and Real Estate [Member] \| Fair Value, Measurements, Recurring \| Preferred Stocks
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	15,900,000		15,600,000
Finance, Insurance and Real Estate [Member] \| Fair Value, Measurements, Recurring \| Common Stock [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	600,000		600,000
Finance, Insurance and Real Estate [Member] \| Fair Value, Measurements, Recurring \| Fair Value, Inputs, Level 1 [Member] \| Preferred Stocks
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	0		0
Finance, Insurance and Real Estate [Member] \| Fair Value, Measurements, Recurring \| Fair Value, Inputs, Level 1 [Member] \| Common Stock [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	600,000		600,000
Finance, Insurance and Real Estate [Member] \| Fair Value, Measurements, Recurring \| Fair Value, Inputs, Level 2 [Member] \| Preferred Stocks
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	15,900,000		15,600,000
Finance, Insurance and Real Estate [Member] \| Fair Value, Measurements, Recurring \| Fair Value, Inputs, Level 2 [Member] \| Common Stock [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	0		0
Finance, Insurance and Real Estate [Member] \| Fair Value, Measurements, Recurring \| Fair Value, Inputs, Level 3 [Member] \| Preferred Stocks
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	0		0
Finance, Insurance and Real Estate [Member] \| Fair Value, Measurements, Recurring \| Fair Value, Inputs, Level 3 [Member] \| Common Stock [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	0		0
All Industries Other than Finance, Insurance and Real Estate [Member] \| Fair Value, Measurements, Recurring \| Preferred Stocks
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	10,000,000		9,900,000
All Industries Other than Finance, Insurance and Real Estate [Member] \| Fair Value, Measurements, Recurring \| Common Stock [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	800,000		600,000
All Industries Other than Finance, Insurance and Real Estate [Member] \| Fair Value, Measurements, Recurring \| Fair Value, Inputs, Level 1 [Member] \| Preferred Stocks
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	0		0
All Industries Other than Finance, Insurance and Real Estate [Member] \| Fair Value, Measurements, Recurring \| Fair Value, Inputs, Level 1 [Member] \| Common Stock [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	300,000		200,000
All Industries Other than Finance, Insurance and Real Estate [Member] \| Fair Value, Measurements, Recurring \| Fair Value, Inputs, Level 2 [Member] \| Preferred Stocks
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	7,800,000		7,500,000
All Industries Other than Finance, Insurance and Real Estate [Member] \| Fair Value, Measurements, Recurring \| Fair Value, Inputs, Level 2 [Member] \| Common Stock [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	0		0
All Industries Other than Finance, Insurance and Real Estate [Member] \| Fair Value, Measurements, Recurring \| Fair Value, Inputs, Level 3 [Member] \| Preferred Stocks
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	2,200,000		2,400,000
All Industries Other than Finance, Insurance and Real Estate [Member] \| Fair Value, Measurements, Recurring \| Fair Value, Inputs, Level 3 [Member] \| Common Stock [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	500,000		400,000
Fair Value, Inputs, Net Asset Value [Member] \| Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, Fair Value Disclosure	194,100,000		191,400,000
Derivative Asset			0
Fair Value, Inputs, Net Asset Value [Member] \| Fair Value, Measurements, Recurring \| Investments in Fixed Maturities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities at fair value	0		0
Fair Value, Inputs, Net Asset Value [Member] \| Fair Value, Measurements, Recurring \| U.S. Government and Government Agencies and Authorities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities at fair value	0		0
Fair Value, Inputs, Net Asset Value [Member] \| Fair Value, Measurements, Recurring \| States and Political Subdivisions
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities at fair value	0		0
Fair Value, Inputs, Net Asset Value [Member] \| Fair Value, Measurements, Recurring \| Foreign Governments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities at fair value	0		0
Fair Value, Inputs, Net Asset Value [Member] \| Fair Value, Measurements, Recurring \| Corporate Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities at fair value	0		0
Fair Value, Inputs, Net Asset Value [Member] \| Fair Value, Measurements, Recurring \| Redeemable Preferred Stocks
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities at fair value	0
Fair Value, Inputs, Net Asset Value [Member] \| Fair Value, Measurements, Recurring \| Mandatorily Redeemable Preferred Stock [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities at fair value			0
Fair Value, Inputs, Net Asset Value [Member] \| Fair Value, Measurements, Recurring \| Collateralized Loan Obligations
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities at fair value	0		0
Fair Value, Inputs, Net Asset Value [Member] \| Fair Value, Measurements, Recurring \| Other Mortgage- and Asset-backed
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fixed maturities at fair value	0		0
Fair Value, Inputs, Net Asset Value [Member] \| Fair Value, Measurements, Recurring \| Equity Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	194,100,000		191,400,000
Fair Value, Inputs, Net Asset Value [Member] \| Fair Value, Measurements, Recurring \| Exchange Traded Funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	0		0
Fair Value, Inputs, Net Asset Value [Member] \| Fair Value, Measurements, Recurring \| Partnership Interest [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	194,100,000		191,400,000
Fair Value, Inputs, Net Asset Value [Member] \| Finance, Insurance and Real Estate [Member] \| Fair Value, Measurements, Recurring \| Preferred Stocks
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	0		0
Fair Value, Inputs, Net Asset Value [Member] \| Finance, Insurance and Real Estate [Member] \| Fair Value, Measurements, Recurring \| Common Stock [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	0		0
Fair Value, Inputs, Net Asset Value [Member] \| All Industries Other than Finance, Insurance and Real Estate [Member] \| Fair Value, Measurements, Recurring \| Preferred Stocks
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	0		0
Fair Value, Inputs, Net Asset Value [Member] \| All Industries Other than Finance, Insurance and Real Estate [Member] \| Fair Value, Measurements, Recurring \| Common Stock [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	$ 0		$ 0

Fair Value Measurements - Narra

Fair Value Measurements - Narrative (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Dec. 31, 2023
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Unfunded commitments		$ 195.7
Transfers out of Level 3	$ 13.1
Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, Fair Value Disclosure	7,002.9	7,122.4
Derivative Asset		14.7
Fair Value, Measurements, Recurring \| Fair Value, Inputs, Net Asset Value [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, Fair Value Disclosure	194.1	191.4
Derivative Asset		0
Fair Value, Inputs, Level 3 [Member] \| Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, Fair Value Disclosure	191.9	192.3
Derivative Asset		0
Fair Value, Inputs, Level 1 [Member] \| Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, Fair Value Disclosure	95	107.3
Derivative Asset		0
Fair Value, Inputs, Level 2 [Member] \| Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, Fair Value Disclosure	6,521.9	6,631.4
Derivative Asset		14.7
Partnership Interest [Member] \| Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI, Current	194.1	191.4
Partnership Interest [Member] \| Fair Value, Measurements, Recurring \| Fair Value, Inputs, Net Asset Value [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI, Current	194.1	191.4
Partnership Interest [Member] \| Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Unfunded commitments	193.9
Partnership Interest [Member] \| Fair Value, Inputs, Level 3 [Member] \| Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI, Current	0	0
Partnership Interest [Member] \| Fair Value, Inputs, Level 1 [Member] \| Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI, Current	0	0
Partnership Interest [Member] \| Fair Value, Inputs, Level 2 [Member] \| Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI, Current	0	0
U.S. Government and Government Agencies and Authorities \| Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-Sale	488.4	511.5
U.S. Government and Government Agencies and Authorities \| Fair Value, Measurements, Recurring \| Fair Value, Inputs, Net Asset Value [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-Sale	0	0
U.S. Government and Government Agencies and Authorities \| Fair Value, Inputs, Level 3 [Member] \| Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-Sale	0	0
U.S. Government and Government Agencies and Authorities \| Fair Value, Inputs, Level 1 [Member] \| Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-Sale	85.4	98.8
U.S. Government and Government Agencies and Authorities \| Fair Value, Inputs, Level 2 [Member] \| Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-Sale	403	412.7
States and Political Subdivisions \| Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-Sale	1,355.9	1,401.9
States and Political Subdivisions \| Fair Value, Measurements, Recurring \| Fair Value, Inputs, Net Asset Value [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-Sale	0	0
States and Political Subdivisions \| Fair Value, Inputs, Level 3 [Member] \| Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-Sale	1.4	0.1
States and Political Subdivisions \| Fair Value, Inputs, Level 1 [Member] \| Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-Sale	0	0
States and Political Subdivisions \| Fair Value, Inputs, Level 2 [Member] \| Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-Sale	1,354.5	1,401.8
Foreign Governments \| Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-Sale	4.6	3.8
Foreign Governments \| Fair Value, Measurements, Recurring \| Fair Value, Inputs, Net Asset Value [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-Sale	0	0
Foreign Governments \| Fair Value, Inputs, Level 3 [Member] \| Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-Sale	0	0
Foreign Governments \| Fair Value, Inputs, Level 1 [Member] \| Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-Sale	0	0
Foreign Governments \| Fair Value, Inputs, Level 2 [Member] \| Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-Sale	4.6	3.8
Corporate Debt Securities [Member] \| Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-Sale	3,635.6	3,690.8
Corporate Debt Securities [Member] \| Fair Value, Measurements, Recurring \| Fair Value, Inputs, Net Asset Value [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-Sale	0	0
Corporate Debt Securities [Member] \| Fair Value, Inputs, Level 3 [Member] \| Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-Sale	180.5	177.1
Corporate Debt Securities [Member] \| Fair Value, Inputs, Level 1 [Member] \| Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-Sale	0	0
Corporate Debt Securities [Member] \| Fair Value, Inputs, Level 2 [Member] \| Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-Sale	3,455.1	3,513.7
Redeemable Preferred Stocks \| Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-Sale	8	8.3
Redeemable Preferred Stocks \| Fair Value, Measurements, Recurring \| Fair Value, Inputs, Net Asset Value [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-Sale	0
Redeemable Preferred Stocks \| Fair Value, Inputs, Level 3 [Member] \| Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-Sale	2.2
Redeemable Preferred Stocks \| Fair Value, Inputs, Level 1 [Member] \| Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-Sale	0
Redeemable Preferred Stocks \| Fair Value, Inputs, Level 2 [Member] \| Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-Sale	5.8
Collateralized Loan Obligations \| Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-Sale	938.2	949.8
Collateralized Loan Obligations \| Fair Value, Measurements, Recurring \| Fair Value, Inputs, Net Asset Value [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-Sale	0	0
Collateralized Loan Obligations \| Fair Value, Inputs, Level 3 [Member] \| Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-Sale	0	0
Collateralized Loan Obligations \| Fair Value, Inputs, Level 1 [Member] \| Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-Sale	0	0
Collateralized Loan Obligations \| Fair Value, Inputs, Level 2 [Member] \| Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-Sale	938.2	949.8
Other Mortgage- and Asset-backed \| Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-Sale	340.9	315.8
Other Mortgage- and Asset-backed \| Fair Value, Measurements, Recurring \| Fair Value, Inputs, Net Asset Value [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-Sale	0	0
Other Mortgage- and Asset-backed \| Fair Value, Inputs, Level 3 [Member] \| Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-Sale	5.1	5.2
Other Mortgage- and Asset-backed \| Fair Value, Inputs, Level 1 [Member] \| Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-Sale	0	0
Other Mortgage- and Asset-backed \| Fair Value, Inputs, Level 2 [Member] \| Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-Sale	335.8	310.6
Investments in Fixed Maturities \| Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-Sale	6,771.6	6,881.9
Investments in Fixed Maturities \| Fair Value, Measurements, Recurring \| Fair Value, Inputs, Net Asset Value [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-Sale	0	0
Investments in Fixed Maturities \| Fair Value, Inputs, Level 3 [Member] \| Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-Sale	189.2	189.5
Investments in Fixed Maturities \| Fair Value, Inputs, Level 1 [Member] \| Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-Sale	85.4	98.8
Investments in Fixed Maturities \| Fair Value, Inputs, Level 2 [Member] \| Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt Securities, Available-for-Sale	6,497	6,593.6
Preferred Stocks \| Fair Value, Measurements, Recurring \| Finance, Insurance and Real Estate [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI, Current	15.9	15.6
Preferred Stocks \| Fair Value, Measurements, Recurring \| Finance, Insurance and Real Estate [Member] \| Fair Value, Inputs, Net Asset Value [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI, Current	0	0
Preferred Stocks \| Fair Value, Measurements, Recurring \| All Industries Other than Finance, Insurance and Real Estate [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI, Current	10	9.9
Preferred Stocks \| Fair Value, Measurements, Recurring \| All Industries Other than Finance, Insurance and Real Estate [Member] \| Fair Value, Inputs, Net Asset Value [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI, Current	0	0
Preferred Stocks \| Fair Value, Inputs, Level 3 [Member] \| Fair Value, Measurements, Recurring \| Finance, Insurance and Real Estate [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI, Current	0	0
Preferred Stocks \| Fair Value, Inputs, Level 3 [Member] \| Fair Value, Measurements, Recurring \| All Industries Other than Finance, Insurance and Real Estate [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI, Current	2.2	2.4
Preferred Stocks \| Fair Value, Inputs, Level 1 [Member] \| Fair Value, Measurements, Recurring \| Finance, Insurance and Real Estate [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI, Current	0	0
Preferred Stocks \| Fair Value, Inputs, Level 1 [Member] \| Fair Value, Measurements, Recurring \| All Industries Other than Finance, Insurance and Real Estate [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI, Current	0	0
Preferred Stocks \| Fair Value, Inputs, Level 2 [Member] \| Fair Value, Measurements, Recurring \| Finance, Insurance and Real Estate [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI, Current	15.9	15.6
Preferred Stocks \| Fair Value, Inputs, Level 2 [Member] \| Fair Value, Measurements, Recurring \| All Industries Other than Finance, Insurance and Real Estate [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI, Current	7.8	7.5
Common Stock [Member] \| Fair Value, Measurements, Recurring \| Finance, Insurance and Real Estate [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI, Current	0.6	0.6
Common Stock [Member] \| Fair Value, Measurements, Recurring \| Finance, Insurance and Real Estate [Member] \| Fair Value, Inputs, Net Asset Value [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI, Current	0	0
Common Stock [Member] \| Fair Value, Measurements, Recurring \| All Industries Other than Finance, Insurance and Real Estate [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI, Current	0.8	0.6
Common Stock [Member] \| Fair Value, Measurements, Recurring \| All Industries Other than Finance, Insurance and Real Estate [Member] \| Fair Value, Inputs, Net Asset Value [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI, Current	0	0
Common Stock [Member] \| Fair Value, Inputs, Level 3 [Member] \| Fair Value, Measurements, Recurring \| Finance, Insurance and Real Estate [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI, Current	0	0
Common Stock [Member] \| Fair Value, Inputs, Level 3 [Member] \| Fair Value, Measurements, Recurring \| All Industries Other than Finance, Insurance and Real Estate [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI, Current	0.5	0.4
Common Stock [Member] \| Fair Value, Inputs, Level 1 [Member] \| Fair Value, Measurements, Recurring \| Finance, Insurance and Real Estate [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI, Current	0.6	0.6
Common Stock [Member] \| Fair Value, Inputs, Level 1 [Member] \| Fair Value, Measurements, Recurring \| All Industries Other than Finance, Insurance and Real Estate [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI, Current	0.3	0.2
Common Stock [Member] \| Fair Value, Inputs, Level 2 [Member] \| Fair Value, Measurements, Recurring \| Finance, Insurance and Real Estate [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI, Current	0	0
Common Stock [Member] \| Fair Value, Inputs, Level 2 [Member] \| Fair Value, Measurements, Recurring \| All Industries Other than Finance, Insurance and Real Estate [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI, Current	0	0
Exchange Traded Funds [Member] \| Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI, Current	8.7	7.7
Exchange Traded Funds [Member] \| Fair Value, Measurements, Recurring \| Fair Value, Inputs, Net Asset Value [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI, Current	0	0
Exchange Traded Funds [Member] \| Fair Value, Inputs, Level 3 [Member] \| Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI, Current	0	0
Exchange Traded Funds [Member] \| Fair Value, Inputs, Level 1 [Member] \| Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI, Current	8.7	7.7
Exchange Traded Funds [Member] \| Fair Value, Inputs, Level 2 [Member] \| Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI, Current	0	0
Equity Securities \| Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI, Current	230.1	225.8
Equity Securities \| Fair Value, Measurements, Recurring \| Fair Value, Inputs, Net Asset Value [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI, Current	194.1	191.4
Equity Securities \| Fair Value, Inputs, Level 3 [Member] \| Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI, Current	2.7	2.8
Equity Securities \| Fair Value, Inputs, Level 1 [Member] \| Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI, Current	9.6	8.5
Equity Securities \| Fair Value, Inputs, Level 2 [Member] \| Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity Securities, FV-NI, Current	$ 23.7	$ 23.1

Fair Value Measurements - Quant

Fair Value Measurements - Quantitative Information for Level 3 Inputs (Details) $ in Millions	Mar. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value, Equity Method Investments, Entities That Calculate Net Asset Value Per Share, Unfunded Commitments	$ 84.5	$ 85.3
Equity Securities, FV-NI	24.7	32.6
Fair Value, Equity Securities FV-NI, Entities That Calculate Net Asset Value Per Share, Unfunded Commitments	0	0
Unfunded commitments		195.7
Mezzanine Debt
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value, Equity Method Investments, Entities That Calculate Net Asset Value Per Share, Unfunded Commitments	42.6	43.1
Fair Value, Alternative Investments, Entities That Calculate Net Asset Value Per Share, Unfunded Commitments	66.3	67
Senior Debt
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value, Equity Method Investments, Entities That Calculate Net Asset Value Per Share, Unfunded Commitments	39.5	39.9
Fair Value, Alternative Investments, Entities That Calculate Net Asset Value Per Share, Unfunded Commitments	10.8	10.6
Distressed Debt
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value, Equity Method Investments, Entities That Calculate Net Asset Value Per Share, Unfunded Commitments	0	0
Fair Value, Alternative Investments, Entities That Calculate Net Asset Value Per Share, Unfunded Commitments	13	13
Secondary Transactions
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value, Equity Method Investments, Entities That Calculate Net Asset Value Per Share, Unfunded Commitments	1.6	1.7
Fair Value, Alternative Investments, Entities That Calculate Net Asset Value Per Share, Unfunded Commitments	3.1	3.1
Hedge Funds
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value, Equity Method Investments, Entities That Calculate Net Asset Value Per Share, Unfunded Commitments	0	0
Fair Value, Alternative Investments, Entities That Calculate Net Asset Value Per Share, Unfunded Commitments	0	0
Leveraged Buyout
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value, Equity Method Investments, Entities That Calculate Net Asset Value Per Share, Unfunded Commitments	0.6	0.6
Fair Value, Alternative Investments, Entities That Calculate Net Asset Value Per Share, Unfunded Commitments	9.5	10
Equity Funds
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value, Equity Method Investments, Entities That Calculate Net Asset Value Per Share, Unfunded Commitments	0	0
Fair Value, Alternative Investments, Entities That Calculate Net Asset Value Per Share, Unfunded Commitments	6.5	6.5
Real Estate Funds
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value, Equity Method Investments, Entities That Calculate Net Asset Value Per Share, Unfunded Commitments	0	0
Other Funds
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value, Equity Method Investments, Entities That Calculate Net Asset Value Per Share, Unfunded Commitments	0.2	0
Real Estate
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair Value, Alternative Investments, Entities That Calculate Net Asset Value Per Share, Unfunded Commitments	0.2	0.2
Fair Value, Measurements, Recurring
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Investments, Fair Value Disclosure	7,002.9	7,122.4
Derivative Asset		14.7
Cash Flow Hedge Derivative Instrument Assets at Fair Value	1.2
Fair Value, Measurements, Recurring \| Partnership Interest [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Equity Securities, FV-NI, Current	194.1	191.4
Fair Value, Measurements, Recurring \| All Industries Other than Finance, Insurance and Real Estate [Member] \| Preferred Stocks
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Equity Securities, FV-NI, Current	10	9.9
Fair Value, Measurements, Recurring \| All Industries Other than Finance, Insurance and Real Estate [Member] \| Common Stock [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Equity Securities, FV-NI, Current	0.8	0.6
Fair Value, Inputs, Level 3 [Member] \| Partnership Interest [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Unfunded commitments	193.9
Fair Value, Inputs, Level 3 [Member] \| Fair Value, Measurements, Recurring
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Investments, Fair Value Disclosure	191.9	192.3
Derivative Asset		0
Cash Flow Hedge Derivative Instrument Assets at Fair Value	0
Fair Value, Inputs, Level 3 [Member] \| Fair Value, Measurements, Recurring \| Partnership Interest [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Equity Securities, FV-NI, Current	0	0
Fair Value, Inputs, Level 3 [Member] \| Fair Value, Measurements, Recurring \| All Industries Other than Finance, Insurance and Real Estate [Member] \| Preferred Stocks
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Equity Securities, FV-NI, Current	2.2	2.4
Fair Value, Inputs, Level 3 [Member] \| Fair Value, Measurements, Recurring \| All Industries Other than Finance, Insurance and Real Estate [Member] \| Common Stock [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Equity Securities, FV-NI, Current	0.5	0.4
Fair Value, Inputs, Level 1 [Member] \| Fair Value, Measurements, Recurring
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Investments, Fair Value Disclosure	95	107.3
Derivative Asset		0
Cash Flow Hedge Derivative Instrument Assets at Fair Value	0
Fair Value, Inputs, Level 1 [Member] \| Fair Value, Measurements, Recurring \| Partnership Interest [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Equity Securities, FV-NI, Current	0	0
Fair Value, Inputs, Level 1 [Member] \| Fair Value, Measurements, Recurring \| All Industries Other than Finance, Insurance and Real Estate [Member] \| Preferred Stocks
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Equity Securities, FV-NI, Current	0	0
Fair Value, Inputs, Level 1 [Member] \| Fair Value, Measurements, Recurring \| All Industries Other than Finance, Insurance and Real Estate [Member] \| Common Stock [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Equity Securities, FV-NI, Current	0.3	0.2
Fair Value, Inputs, Level 2 [Member] \| Fair Value, Measurements, Recurring
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Investments, Fair Value Disclosure	6,521.9	6,631.4
Derivative Asset		14.7
Cash Flow Hedge Derivative Instrument Assets at Fair Value	1.2
Fair Value, Inputs, Level 2 [Member] \| Fair Value, Measurements, Recurring \| Partnership Interest [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Equity Securities, FV-NI, Current	0	0
Fair Value, Inputs, Level 2 [Member] \| Fair Value, Measurements, Recurring \| All Industries Other than Finance, Insurance and Real Estate [Member] \| Preferred Stocks
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Equity Securities, FV-NI, Current	7.8	7.5
Fair Value, Inputs, Level 2 [Member] \| Fair Value, Measurements, Recurring \| All Industries Other than Finance, Insurance and Real Estate [Member] \| Common Stock [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Equity Securities, FV-NI, Current	0	0
Fair Value Measured at Net Asset Value Per Share
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Investments, Fair Value Disclosure	413.9	417.9
Equity Method Investments, Fair Value Disclosure	215.2	221.7
Alternative Investment	194.1	191.4
Fair Value, Alternative Investments, Entities That Calculate Net Asset Value Per Share, Unfunded Commitments	109.4	110.4
Equity Securities, FV-NI	4.6	4.8
Fair Value Measured at Net Asset Value Per Share \| Mezzanine Debt
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Equity Method Investments, Fair Value Disclosure	123.2	125.4
Alternative Investment	127.7	124
Fair Value Measured at Net Asset Value Per Share \| Senior Debt
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Equity Method Investments, Fair Value Disclosure	19.2	19
Alternative Investment	24.7	24.8
Fair Value Measured at Net Asset Value Per Share \| Distressed Debt
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Equity Method Investments, Fair Value Disclosure	6.1	7.9
Alternative Investment	12.9	12.4
Fair Value Measured at Net Asset Value Per Share \| Secondary Transactions
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Equity Method Investments, Fair Value Disclosure	6.8	7.9
Alternative Investment	2.7	2.8
Fair Value Measured at Net Asset Value Per Share \| Hedge Funds
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Equity Method Investments, Fair Value Disclosure	0.1	0.1
Alternative Investment	0	1.9
Fair Value Measured at Net Asset Value Per Share \| Leveraged Buyout
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Equity Method Investments, Fair Value Disclosure	8.5	8.6
Alternative Investment	19.7	19
Fair Value Measured at Net Asset Value Per Share \| Equity Funds
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Equity Method Investments, Fair Value Disclosure	0.8	1.2
Alternative Investment	6.3	6.4
Fair Value Measured at Net Asset Value Per Share \| Real Estate Funds
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Equity Method Investments, Fair Value Disclosure	42	41.9
Fair Value Measured at Net Asset Value Per Share \| Other Funds
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Equity Method Investments, Fair Value Disclosure	8.5	9.7
Fair Value Measured at Net Asset Value Per Share \| Real Estate
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Alternative Investment	0.1	0.1
Fair Value Measured at Net Asset Value Per Share \| Fair Value, Measurements, Recurring
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Cash Flow Hedge Derivative Instrument Assets at Fair Value	0
Fair Value, Inputs, Net Asset Value [Member] \| Fair Value, Measurements, Recurring
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Investments, Fair Value Disclosure	194.1	191.4
Derivative Asset		0
Fair Value, Inputs, Net Asset Value [Member] \| Fair Value, Measurements, Recurring \| Partnership Interest [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Equity Securities, FV-NI, Current	194.1	191.4
Fair Value, Inputs, Net Asset Value [Member] \| Fair Value, Measurements, Recurring \| All Industries Other than Finance, Insurance and Real Estate [Member] \| Preferred Stocks
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Equity Securities, FV-NI, Current	0	0
Fair Value, Inputs, Net Asset Value [Member] \| Fair Value, Measurements, Recurring \| All Industries Other than Finance, Insurance and Real Estate [Member] \| Common Stock [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Equity Securities, FV-NI, Current	$ 0	$ 0
Senior Debt Obligations [Member] \| Measurement Input, Discount Rate \| Non-investment-grade \| Market Yield \| Minimum \| Fair Value, Inputs, Level 3 [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Debt instrument, measurement input	0.070	0.092
Senior Debt Obligations [Member] \| Measurement Input, Discount Rate \| Non-investment-grade \| Market Yield \| Maximum \| Fair Value, Inputs, Level 3 [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Debt instrument, measurement input	0.480	0.367
Senior Debt Obligations [Member] \| Measurement Input, Discount Rate \| Non-investment-grade \| Market Yield \| Weighted Average [Member] \| Fair Value, Inputs, Level 3 [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Debt instrument, measurement input	0.130	0.135
Junior Subordinated Debt [Member] \| Measurement Input, Discount Rate \| Non-investment-grade \| Market Yield \| Minimum \| Fair Value, Inputs, Level 3 [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Debt instrument, measurement input	0.110	0.118
Junior Subordinated Debt [Member] \| Measurement Input, Discount Rate \| Non-investment-grade \| Market Yield \| Maximum \| Fair Value, Inputs, Level 3 [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Debt instrument, measurement input	0.255	0.225
Junior Subordinated Debt [Member] \| Measurement Input, Discount Rate \| Non-investment-grade \| Market Yield \| Weighted Average [Member] \| Fair Value, Inputs, Level 3 [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Debt instrument, measurement input	0.132	0.138
Private Placement \| External Credit Rating, Investment Grade [Member] \| Market Yield \| Fair Value, Inputs, Level 3 [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Assets, Fair Value Disclosure	$ 55.3	$ 60
Private Placement \| Measurement Input, Discount Rate \| External Credit Rating, Investment Grade [Member] \| Market Yield \| Minimum \| Fair Value, Inputs, Level 3 [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Alternative investment, measurement input	0.018	0.042
Private Placement \| Measurement Input, Discount Rate \| External Credit Rating, Investment Grade [Member] \| Market Yield \| Maximum \| Fair Value, Inputs, Level 3 [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Alternative investment, measurement input	0.135	0.158
Private Placement \| Measurement Input, Discount Rate \| External Credit Rating, Investment Grade [Member] \| Market Yield \| Weighted Average [Member] \| Fair Value, Inputs, Level 3 [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Alternative investment, measurement input	0.079	0.087
Senior Debt Obligations [Member] \| Non-investment-grade \| Market Yield \| Fair Value, Inputs, Level 3 [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Assets, Fair Value Disclosure	$ 31.7	$ 32.6
Junior Subordinated Debt [Member] \| Non-investment-grade \| Market Yield \| Fair Value, Inputs, Level 3 [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Assets, Fair Value Disclosure	35.8	32.5
Other Debt Obligations [Member] \| Market Yield \| Fair Value, Inputs, Level 3 [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Assets, Fair Value Disclosure	66.4	64.4
Investments in Fixed Maturities \| Market Yield \| Fair Value, Inputs, Level 3 [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Assets, Fair Value Disclosure	$ 189.2	$ 189.5

Fair Value Measurements - Level

Fair Value Measurements - Level 3 Inputs Reconciliation (Details) - USD ($)	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023	Dec. 31, 2022
Fair Value, Assets and Liabilities Measured on Recurring Basis, Gain (Loss) Included in Earnings [Abstract]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	$ 191,900,000	$ 210,200,000	$ 192,300,000	$ 230,000,000
Included in Condensed Consolidated Statement of Operations	(300,000)	(100,000)
Included in Other Comprehensive Income (Loss)	1,800,000	1,700,000
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases	13,200,000	19,400,000
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales	(3,700,000)	(41,200,000)
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Transfers Into Level 3	1,700,000	400,000
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3	(13,100,000)
Corporate Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis, Gain (Loss) Included in Earnings [Abstract]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	180,500,000	196,100,000	177,100,000	216,000,000
Included in Condensed Consolidated Statement of Operations	(200,000)	400,000
Included in Other Comprehensive Income (Loss)	2,300,000	1,500,000
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases	13,200,000	19,400,000
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales	(3,700,000)	(41,200,000)
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Transfers Into Level 3	0	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3	(8,200,000)
States and Political Subdivisions
Fair Value, Assets and Liabilities Measured on Recurring Basis, Gain (Loss) Included in Earnings [Abstract]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	1,400,000		100,000
Included in Condensed Consolidated Statement of Operations	0
Included in Other Comprehensive Income (Loss)	(400,000)
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Transfers Into Level 3	1,700,000
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3	0
Mandatorily Redeemable Preferred Stock [Member]
Fair Value, Assets and Liabilities Measured on Recurring Basis, Gain (Loss) Included in Earnings [Abstract]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	2,200,000	6,800,000	7,100,000	6,800,000
Included in Condensed Consolidated Statement of Operations	0	0
Included in Other Comprehensive Income (Loss)	0	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases	0	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales	0	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Transfers Into Level 3	0	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3	(4,900,000)
Other Mortgage- and Asset-backed
Fair Value, Assets and Liabilities Measured on Recurring Basis, Gain (Loss) Included in Earnings [Abstract]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	5,100,000	5,300,000	5,200,000	5,100,000
Included in Condensed Consolidated Statement of Operations	0	0
Included in Other Comprehensive Income (Loss)	(100,000)	200,000
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases	0	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales	0	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Transfers Into Level 3	0	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3	0
Equity Securities
Fair Value, Assets and Liabilities Measured on Recurring Basis, Gain (Loss) Included in Earnings [Abstract]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	2,700,000	2,000,000	$ 2,800,000	$ 2,100,000
Included in Condensed Consolidated Statement of Operations	(100,000)	(500,000)
Included in Other Comprehensive Income (Loss)	0	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases	0	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales	0	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Transfers Into Level 3	0	$ 400,000
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3	$ 0

Fair Value Measurements - Balan

Fair Value Measurements - Balance Sheet Grouping (Details) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Balance Sheet Related Disclosures [Abstract]
Loans, Gross, Insurance Policy		$ 281.2
Short-Term Investments	$ 520.7	520.9
Mortgage Loans on Real Estate, Commercial and Consumer, Net	93.1	99.8
Long-Term Debt	1,389.8	1,389.2
Policyholder Obligations	660.9	655.7
Loans to Policyholders	280.5
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Abstract]
Other Short-term Investments, Fair Value Disclosure	520.7	520.9
Long-term debt, fair value	1,246.8
Company-Owned Life Insurance	515.7	513.5
Equity Securities at Modified Cost	24.7	32.6
Equity Securities, FV-NI	24.7	32.6
Fair Value Measured at Net Asset Value Per Share
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Abstract]
Equity Securities, FV-NI	4.6	4.8
Fair Value, Alternative Investments, Entities That Calculate Net Asset Value Per Share, Unfunded Commitments	109.4	110.4
Federal Home Loan Bank of Chicago
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Abstract]
Federal Home Loan Bank Borrowings, Fair Value Disclosure	563.2	557.4
Loans To Policyholders [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Abstract]
Loans	280.5	281.2
Mortgage Loans [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Abstract]
Loans	93.1	99.8
United Insurance Company of America \| Federal Home Loan Bank of Chicago
Balance Sheet Related Disclosures [Abstract]
Policyholder Obligations	563.2	557.4
United Insurance Company of America \| FHLB Funding Agreements \| Federal Home Loan Bank of Chicago
Balance Sheet Related Disclosures [Abstract]
Policyholder Obligations	$ 563.2	$ 557.4

Variable Interest Entities (Det

Variable Interest Entities (Details) - USD ($) $ in Millions	3 Months Ended		12 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023
Schedule of Equity Method Investments [Line Items]
Income Tax Expense (Benefit)	$ 16.4	$ (23.8)
Surplus Notes and Guarantee Fund Certificates, Reciprocal Exchange	6		$ 4
Surplus Notes and Guarantee Fund Certificates, Additional Reciprocal Exchange	2
Variable Interest Entity, Not Primary Beneficiary
Schedule of Equity Method Investments [Line Items]
Proceeds from Equity Method Investment, Distribution	0.5	0.5
Income from Change in Value of Alternative Energy Partnership Investments	0.4	0.7
Income Tax Credits and Adjustments	0	(0.1)
Income Tax Expense (Benefit)	(0.1)	$ (0.2)
Cash and Cash Equivalents, at Carrying Value	2.7		2.7
Property, Plant and Equipment, Net	255		256.2
Other Assets	7.5		7.5
Assets	265.2		266.4
Variable Interest Entity, Reporting Entity Involvement, Maximum Loss Exposure, Amount	$ 17.2		$ 17.3

Deferred Costs, Capitalized, _3

Deferred Costs, Capitalized, Prepaid, and Other Assets (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Movement Analysis of Deferred Policy Acquisition Costs [Roll Forward]
Deferred Policy Acquisition Cost, Beginning Balance	$ 591.6	$ 635.6
Deferred Policy Acquisition Cost, Capitalization	135.8	164.9
Deferred Policy Acquisition Costs, Amortization Expense	(130.7)	(147.9)
Deferred Policy Acquisition Cost, Experience Adjustment	(1.4)	(1.1)
Deferred Policy Acquisition Cost, Ending Balance	595.3	651.5
Term Life Insurance
Movement Analysis of Deferred Policy Acquisition Costs [Roll Forward]
Deferred Policy Acquisition Cost, Capitalization	15.8	15.4
Deferred Policy Acquisition Costs, Amortization Expense	(5.3)	(5.6)
Deferred Policy Acquisition Cost, Experience Adjustment	(1.4)	(1.1)
Property and Casualty Insurance Reserves
Movement Analysis of Deferred Policy Acquisition Costs [Roll Forward]
Deferred Policy Acquisition Cost, Beginning Balance	164.9	231.1
Deferred Policy Acquisition Cost, Capitalization	120	149.5
Deferred Policy Acquisition Costs, Amortization Expense	(125.4)	(142.3)
Deferred Policy Acquisition Cost, Experience Adjustment	0	0
Deferred Policy Acquisition Cost, Ending Balance	159.5	238.3
Life Insurance
Movement Analysis of Deferred Policy Acquisition Costs [Roll Forward]
Deferred Policy Acquisition Cost, Beginning Balance	426.7	404.5
Deferred Policy Acquisition Cost, Ending Balance	$ 435.8	$ 413.2

Receivables from Policyholder_3

Receivables from Policyholders - Allowance for Expected Credit Losses (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Premium Receivable, Allowance for Credit Loss [Roll Forward]
Balance, Beginning of Year	$ 13.9	$ 13.1
Provision for Expected Credit Losses	6.5	11
Write-offs of Uncollectible Receivables from Policyholders	(14)	(12.8)
Balance, End of Period	6.4	11.3
Receivable Balance, End of Period	953.1	1,344
Operating Segments
Premium Receivable, Allowance for Credit Loss [Roll Forward]
Receivable Balance, End of Period
Corporate and Other
Premium Receivable, Allowance for Credit Loss [Roll Forward]
Balance, Beginning of Year	1	0.8
Provision for Expected Credit Losses	0.2	0.4
Write-offs of Uncollectible Receivables from Policyholders	(0.2)	(0.5)
Balance, End of Period	1	0.7
Receivable Balance, End of Period	49.8	101.6
Specialty and Life Segments \| Operating Segments
Premium Receivable, Allowance for Credit Loss [Roll Forward]
Balance, Beginning of Year	12.9	12.3
Provision for Expected Credit Losses	6.3	10.6
Write-offs of Uncollectible Receivables from Policyholders	(13.8)	(12.3)
Balance, End of Period	5.4	10.6
Receivable Balance, End of Period	903.3	1,242.4
Speciality \| Operating Segments
Premium Receivable, Allowance for Credit Loss [Roll Forward]
Balance, Beginning of Year	12.9	12.3
Provision for Expected Credit Losses	6.2	10.3
Write-offs of Uncollectible Receivables from Policyholders	(13.7)	(12)
Balance, End of Period	5.4	10.6
Receivable Balance, End of Period	892.8	1,232.7
Life Segment \| Operating Segments
Premium Receivable, Allowance for Credit Loss [Roll Forward]
Balance, Beginning of Year	0	0
Provision for Expected Credit Losses	0.1	0.3
Write-offs of Uncollectible Receivables from Policyholders	(0.1)	(0.3)
Balance, End of Period	0	0
Receivable Balance, End of Period	$ 10.5	$ 9.7

Other Comprehensive Income an_3

Other Comprehensive Income and Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023	Dec. 31, 2022
Stockholders' Equity Attributable to Parent	$ 2,589.8		$ 2,505.2
Accumulated Other Comprehensive (Income) Loss, Defined Benefit Plan, after Tax			9.5	$ (37.2)
AOCI, Cash Flow Hedge, Cumulative Gain (Loss), after Tax			2.5	2.8
AOCI, Liability for Future Policy Benefit, Expected Future Policy Benefit, before Tax	160.6	$ 241.1
AOCI, Accumulated Gain (Loss), Debt Securities, Available-for-sale, Parent [Member]
Stockholders' Equity Attributable to Parent	(1.1)	(2.2)	(2.5)	(2.2)
OCI, before Reclassifications, Net of Tax, Attributable to Parent	1.6	1.4
Reclassification from AOCI, Current Period, Tax	0.2	0.4
Reclassification from AOCI, Current Period, Net of Tax, Attributable to Parent	(0.2)	(1.4)
Other Comprehensive Income (Loss), Tax, Portion Attributable to Parent	0.1	(0.4)
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	1.4	0
AOCI Attributable to Parent [Member]
Stockholders' Equity Attributable to Parent	(335)	(454.7)	(360.8)	(514.9)
OCI, before Reclassifications, Net of Tax, Attributable to Parent	17	62.2
Reclassification from AOCI, Current Period, Tax	(2.3)	0.4
Reclassification from AOCI, Current Period, Net of Tax, Attributable to Parent	8.8	(2)
Other Comprehensive Income (Loss), Tax, Portion Attributable to Parent	(6.7)	(17.1)
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	25.8	60.2
Accumulated Defined Benefit Plans Adjustment Attributable to Parent [Member]
Stockholders' Equity Attributable to Parent	8.7	(37.6)
OCI, before Reclassifications, Net of Tax, Attributable to Parent	0	0
Reclassification from AOCI, Current Period, Tax	0.1	(0.1)
Reclassification from AOCI, Current Period, Net of Tax, Attributable to Parent	(0.8)	(0.4)
Other Comprehensive Income (Loss), Tax, Portion Attributable to Parent	0.1	0
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	(0.8)	(0.4)
Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent [Member]
Stockholders' Equity Attributable to Parent	2.5	2.7
OCI, before Reclassifications, Net of Tax, Attributable to Parent	0	0
Reclassification from AOCI, Current Period, Tax	0	0.1
Reclassification from AOCI, Current Period, Net of Tax, Attributable to Parent	0	(0.1)
Other Comprehensive Income (Loss), Tax, Portion Attributable to Parent	0	0
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	0	(0.1)
AOCI, Gain (Loss), Debt Securities, Available-for-sale, with Allowance for Credit Loss, Parent
Stockholders' Equity Attributable to Parent	(617.2)	(572)	$ (530.9)	$ (719.4)
OCI, before Reclassifications, Net of Tax, Attributable to Parent	(96.1)	147.5
Reclassification from AOCI, Current Period, Tax	(2.6)	0
Reclassification from AOCI, Current Period, Net of Tax, Attributable to Parent	9.8	(0.1)
Other Comprehensive Income (Loss), Tax, Portion Attributable to Parent	22.7	(39.8)
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	(86.3)	147.4
AOCI, Liability for Future Policy Benefit, Parent
Stockholders' Equity Attributable to Parent	272.1	154.4
OCI, before Reclassifications, Net of Tax, Attributable to Parent	111.5	(86.7)
Reclassification from AOCI, Current Period, Tax	0	0
Reclassification from AOCI, Current Period, Net of Tax, Attributable to Parent	0	0
Other Comprehensive Income (Loss), Tax, Portion Attributable to Parent	(29.6)	23.1
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	$ 111.5	$ (86.7)

Stockholders_ Equity - Narrativ

Stockholders’ Equity - Narrative (Details) - USD ($)	3 Months Ended
Stockholders’ Equity - Narrative (Details) - USD ($)	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2022	May 06, 2020	Aug. 06, 2014
Class of Stock [Line Items]
Value of additional shares authorized to be repurchased				$ 200,000,000
Remaining authorized repurchase amount	$ 171,600,000		$ 333,300,000		$ 133,300,000
Employee Stock Purchase Plan \| Share-based Payment Arrangement
Class of Stock [Line Items]
Shares issued under employee stock purchase plan (in shares)	15,000	18,000
Price per share (in dollars per share)	$ 52.63	$ 46.46
Employee Stock Purchase Plan \| Employee Stock Option
Class of Stock [Line Items]
Compensation costs	$ 100,000	$ 200,000

Policyholder Contract Liabili_3

Policyholder Contract Liabilities - Policyholder Contract Liabilities (Details) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Policyholder Obligations	$ 660.9	$ 655.7
United Insurance Company of America \| Federal Home Loan Bank of Chicago
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Policyholder Obligations	563.2	557.4
FHLB of Chicago Common Stock Owned at Cost	16.3	16.6
FHLB Funding Agreements \| United Insurance Company of America \| Federal Home Loan Bank of Chicago
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Policyholder Obligations	563.2	557.4
Universal Life-type Policyholder Account Balances
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Policyholder Obligations	$ 97.7	$ 98.3

Policyholder Contract Liabili_4

Policyholder Contract Liabilities - Narrative (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Dec. 31, 2023
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Policyholder Account Balance, Weighted Average Crediting Rate	5.10%
Liabilities for Guarantees on Long-Duration Contracts, Guaranteed Benefit Liability, Net	$ 289.2	$ 294.1
Policyholder Account Balance, Cash Surrender Value	97.7	$ 98.2
United Insurance Company of America \| Federal Home Loan Bank of Chicago
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Federal Home Loan Bank, amount of advances	25
Payments of FHLBank borrowings	$ 19.2

Policyholder Contract Liabili_5

Policyholder Contract Liabilities - Supplemental Financial Information (Details) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Policyholder Obligations	$ 660.9	$ 655.7
Federal Home Loan Bank of Chicago \| United Insurance Company of America
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Policyholder Obligations	563.2	557.4
Fair Value of Collateral Pledged	712.1	629.3
Federal Home Loan Bank of Chicago \| United Insurance Company of America \| FHLB Funding Agreements
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items]
Policyholder Obligations	$ 563.2	$ 557.4

Debt - Narrative (Details)

Debt - Narrative (Details)			1 Months Ended	3 Months Ended
Debt - Narrative (Details)	Mar. 10, 2022 USD ($) deferral_period	Jun. 04, 2019 USD ($)	Mar. 31, 2021 USD ($)	Mar. 31, 2024 USD ($)	Mar. 31, 2023 USD ($)	Dec. 31, 2023 USD ($)	Feb. 15, 2022 USD ($)	Sep. 22, 2020 USD ($)	Jun. 08, 2018 USD ($)	Feb. 28, 2015 USD ($)
Debt Instrument [Line Items]
Long-Term Debt				$ 1,389,800,000		$ 1,389,200,000
Interest and other expenses				14,000,000	$ 14,100,000
Interest paid, including capitalized interest, operating and investing activities				20,000,000	$ 24,800,000
Derivative, Gain on Derivative				5,900,000
Senior Notes, 2.400 Percent Due September 30, 2030
Debt Instrument [Line Items]
Long-Term Debt								$ 395,800,000
Senior Notes, 3.800 Percent Due February 23, 2033
Debt Instrument [Line Items]
Long-Term Debt							$ 395,100,000
5.875% Fixed-Rate Reset Junior Subordinated Debentures due 2062
Debt Instrument [Line Items]
Long-Term Debt	$ 144,700,000
Senior Notes \| Senior Notes, 4.35 Percent Due February 15, 2025
Debt Instrument [Line Items]
Long-Term Debt				$ 0		449,600,000
Stated interest rate				4.35%
Long-term debt, gross				$ 450,000,000
Face amount of debt										$ 250,000,000
Increase in senior notes			$ 200,000,000
Senior Notes \| Senior Notes, 2.400 Percent Due September 30, 2030
Debt Instrument [Line Items]
Long-Term Debt				397,100,000		397,000,000
Stated interest rate								2.40%
Long-term debt, gross				400,000,000
Effective interest rate								2.52%
Senior Notes \| Senior Notes, 3.800 Percent Due February 23, 2033
Debt Instrument [Line Items]
Long-Term Debt				396,100,000		396,000,000
Stated interest rate							3.80%
Long-term debt, gross				400,000,000
Effective interest rate								3.95%
Senior Notes \| 5.875% Fixed-Rate Reset Junior Subordinated Debentures due 2062
Debt Instrument [Line Items]
Long-Term Debt				146,900,000		$ 146,600,000
Long-term debt, gross				150,000,000
Junior Subordinated Debt [Member] \| 5.875% Fixed-Rate Reset Junior Subordinated Debentures due 2062
Debt Instrument [Line Items]
Stated interest rate	5.875%
Debt Instrument, Basis Spread on Variable Rate	4.14%
Debt Instrument, Interest Deferrals, Number Of Deferral Periods \| deferral_period	1
Debt Instrument, Interest Deferrals, Period	5 years
Revolving Credit Facility \| Notes Payable under Revolving Credit Agreement \| Second Amended and Restated Credit Agreement
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity		$ 800,000,000		424,000,000					$ 600,000,000
Increase in revolving credit borrowing capacity		$ 200,000,000
Line of credit facility, amount outstanding				$ 0

Debt - Long Term Debt (Details)

Debt - Long Term Debt (Details) - USD ($) $ in Millions	3 Months Ended
Debt - Long Term Debt (Details) - USD ($) $ in Millions	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023	Mar. 10, 2022	Feb. 15, 2022	Sep. 22, 2020
Debt Instrument [Line Items]
Long-Term Debt	$ 1,389.8		$ 1,389.2
Derivative, Gain (Loss) on Derivative, Net	0.5
Gain (Loss) on Derivative Instruments, Net, Pretax	0.1	$ 0.1
Senior Notes, 2.400 Percent Due September 30, 2030
Debt Instrument [Line Items]
Long-Term Debt						$ 395.8
Senior Notes, 3.800 Percent Due February 23, 2033
Debt Instrument [Line Items]
Long-Term Debt					$ 395.1
5.875% Fixed-Rate Reset Junior Subordinated Debentures due 2062
Debt Instrument [Line Items]
Long-Term Debt				$ 144.7
Senior Notes \| Senior Notes, 4.35 Percent Due February 15, 2025
Debt Instrument [Line Items]
Long-Term Debt	$ 0		449.6
Stated interest rate	4.35%
Long-term Debt, Current, at Amortized Cost (Fair Value: 2024 - $443.4; 2023 - $—)	$ 449.7		0
Senior Notes \| Senior Notes, 2.400 Percent Due September 30, 2030
Debt Instrument [Line Items]
Long-Term Debt	397.1		397
Stated interest rate						2.40%
Senior Notes \| Senior Notes, 3.800 Percent Due February 23, 2033
Debt Instrument [Line Items]
Long-Term Debt	396.1		396
Stated interest rate					3.80%
Senior Notes \| 5.875% Fixed-Rate Reset Junior Subordinated Debentures due 2062
Debt Instrument [Line Items]
Long-Term Debt	$ 146.9		$ 146.6
Junior Subordinated Debt [Member] \| 5.875% Fixed-Rate Reset Junior Subordinated Debentures due 2062
Debt Instrument [Line Items]
Stated interest rate				5.875%

Leases - Narrative (Details)

Leases - Narrative (Details)	Mar. 31, 2024
Minimum \| Building
Lessee, Lease, Description [Line Items]
Lessee, operating lease, term of contract	1 year
Minimum \| Equipment
Lessee, Lease, Description [Line Items]
Lessee, operating lease, term of contract	1 year
Maximum \| Building
Lessee, Lease, Description [Line Items]
Lessee, operating lease, term of contract	15 years
Maximum \| Equipment
Lessee, Lease, Description [Line Items]
Lessee, operating lease, term of contract	5 years

Leases - Right of Use Assets an

Leases - Right of Use Assets and Liabilities (Details) (Details) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Leases [Abstract]
Operating Lease Right-of-Use Assets	$ 36.1	$ 38.4
Operating Lease Liabilities	$ 58.3	$ 62.3

Leases - Lease Cost (Details)

Leases - Lease Cost (Details) - USD ($) $ in Millions	3 Months Ended
Leases - Lease Cost (Details) - USD ($) $ in Millions	Mar. 31, 2024	Mar. 31, 2023
Lease Cost
Operating Lease Cost	$ 3.9	$ 4.1
Variable Lease, Cost	1.1	0.1
Short-Term Lease Cost	0	0
Total Lease Expense	5	4.2
Lease, Cost	$ 5	$ 4.2

Leases - Lease Weighted Average

Leases - Lease Weighted Average (Details)	Mar. 31, 2024	Mar. 31, 2023
Leases [Abstract]
Weighted-average Remaining Lease Term - Operating Leases	5 years 6 months	5 years 7 months 6 days
Weighted-average Discount Rate - Operating Leases	4.30%	3.60%

Leases - Future Minimum Lease P

Leases - Future Minimum Lease Payments Under Operating Leases (Details) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract]
Remainder of 2024	$ 15
2025	15.7
2026	9.7
2027	7.4
2028	4.7
2029 and Thereafter	15.2
Total Future Payments	67.7
Less: Discount	9.4
Present Value of Minimum Lease Payments	$ 58.3	$ 62.3

Income Taxes - Narrative (Detai

Income Taxes - Narrative (Details) - USD ($)	3 Months Ended
Income Taxes - Narrative (Details) - USD ($)	Mar. 31, 2024	Mar. 31, 2023
Income Tax Disclosure [Abstract]
Income Tax Expense (Benefit) Attributable to Kemper Corporation	$ 16,800,000
Income Tax Expense (Benefit)	$ 16,400,000	$ (23,800,000)
Effective Income Tax Rate Reconciliation, Percent	19.10%	(22.90%)
Unrecognized tax benefits	$ 0
Interest Paid, Excluding Capitalized Interest, Operating Activities	$ 10,400,000	$ 124,700,000