Affiliated Managers (MGR) 10-Q5 Nov 212021 Q3 Quarterly reportFinancial data

Company Profile

Cover Page

Cover Page - shares	9 Months Ended
Cover Page - shares	Sep. 30, 2021	Nov. 03, 2021
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Sep. 30, 2021
Document Transition Report	false
Entity File Number	001-13459
Entity Registrant Name	AFFILIATED MANAGERS GROUP, INC.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	04-3218510
Entity Address, Address Line One	777 South Flagler Drive
Entity Address, City or Town	West Palm Beach
Entity Address, State or Province	FL
Entity Address, Postal Zip Code	33401
City Area Code	800
Local Phone Number	345-1100
Entity Information [Line Items]
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)		40,651,314
Entity Central Index Key	0001004434
Amendment Flag	false
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	Q3
Common Stock ($0.01 par value)
Entity Information [Line Items]
Title of 12(b) Security	Common Stock ($0.01 par value)
Trading Symbol	AMG
Security Exchange Name	NYSE
2059 Junior Subordinated Notes
Entity Information [Line Items]
Title of 12(b) Security	5.875% Junior Subordinated Notes due 2059
Trading Symbol	MGR
Security Exchange Name	NYSE
4.750% Junior Subordinated Notes due 2060
Entity Information [Line Items]
Title of 12(b) Security	4.750% Junior Subordinated Notes due 2060
Trading Symbol	MGRB
Security Exchange Name	NYSE
4.200% Junior Subordinated Notes due 2061
Entity Information [Line Items]
Title of 12(b) Security	4.200% Junior Subordinated Notes due 2061
Trading Symbol	MGRD
Security Exchange Name	NYSE

CONSOLIDATED STATEMENTS OF INCO

CONSOLIDATED STATEMENTS OF INCOME - USD ($) shares in Millions, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Income Statement [Abstract]
Consolidated revenue	$ 575.2	$ 494.8	$ 1,720.6	$ 1,473.2
Consolidated expenses:
Compensation and related expenses	256.4	212.5	752.2	636.9
Selling, general and administrative	82.9	74.1	250.3	237.9
Intangible amortization and impairments	8.9	31.9	25.3	133.4
Interest expense	28.5	23.8	82.8	65.6
Depreciation and other amortization	4	4.6	12.5	14.7
Other expenses (net)	14.6	12.3	40.6	34.6
Total consolidated expenses	395.3	359.2	1,163.7	1,123.1
Equity method income (loss) (net)	35.9	17	125.1	(78.8)
Investment and other income	37.5	12.7	91.1	2.9
Income before income taxes	253.3	165.3	773.1	274.2
Income tax expense	44.9	37.5	166.4	43
Net income	208.4	127.8	606.7	231.2
Net income (non-controlling interests)	(80)	(56.5)	(219.4)	(144.9)
Net income (controlling interest)	$ 128.4	$ 71.3	$ 387.3	$ 86.3
Average shares outstanding (basic) (in shares)	41.1	46.3	41.8	47.1
Average shares outstanding (diluted) (in shares)	44.3	46.5	44.8	47.2
Earnings per share (basic) (in dollars per share)	$ 3.12	$ 1.54	$ 9.28	$ 1.83
Earnings per share (diluted) (in dollars per share)	$ 3	$ 1.53	$ 8.95	$ 1.83

CONSOLIDATED STATEMENTS OF COMP

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Statement of Comprehensive Income [Abstract]
Net income	$ 208.4	$ 127.8	$ 606.7	$ 231.2
Other comprehensive income (loss), net of tax:
Foreign currency translation gain (loss)	(19.7)	24.7	11.7	(51.4)
Change in net realized and unrealized gain (loss) on derivative financial instruments	(1.9)	0.2	(1)	(2.1)
Other comprehensive income (loss), net of tax	(21.6)	24.9	10.7	(53.5)
Comprehensive income	186.8	152.7	617.4	177.7
Comprehensive income (non-controlling interests)	(77.3)	(65.9)	(215.5)	(137.5)
Comprehensive income (controlling interest)	$ 109.5	$ 86.8	$ 401.9	$ 40.2

CONSOLIDATED BALANCE SHEETS

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Assets
Cash and cash equivalents	$ 1,128	$ 1,039.7
Receivables	492.5	421.6
Investments in marketable securities	75.8	74.9
Goodwill	2,658.5	2,661.4
Acquired client relationships (net)	1,018.2	1,048.8
Equity method investments in Affiliates (net)	2,085.2	2,074.8
Fixed assets (net)	74.2	79.6
Other investments	357.1	257.2
Other assets	218.1	230.9
Total assets	8,107.6	7,888.9
Liabilities and Equity
Payables and accrued liabilities	690.2	712.4
Debt	2,491.8	2,312.1
Deferred income tax liability (net)	513.9	423.4
Other liabilities	463.3	452.2
Total liabilities	4,159.2	3,900.1
Commitments and contingencies (Note 9)
Redeemable non-controlling interests	748.9	671.5
Equity:
Common stock ($0.01 par value, 153.0 shares authorized; 58.5 shares outstanding in 2020 and 2021)	0.6	0.6
Additional paid-in capital	556	728.9
Accumulated other comprehensive loss	(83.7)	(98.3)
Retained earnings	4,391.5	4,005.5
Total stockholders' equity before treasury stock	4,864.4	4,636.7
Less: Treasury stock, at cost (14.5 shares in 2020 and 17.7 shares in 2021)	(2,227.5)	(1,857)
Total stockholders' equity	2,636.9	2,779.7
Non-controlling interests	562.6	537.6
Total equity	3,199.5	3,317.3
Total liabilities and equity	$ 8,107.6	$ 7,888.9

CONSOLIDATED BALANCE SHEETS (Pa

CONSOLIDATED BALANCE SHEETS (Parenthetical) - $ / shares	Sep. 30, 2021	Dec. 31, 2020
Statement of Financial Position [Abstract]
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	153,000,000	153,000,000
Common stock, shares outstanding (in shares)	58,500,000	58,500,000
Treasury stock, at cost (in shares)	17,700,000	14,500,000

CONSOLIDATED STATEMENTS OF CHAN

CONSOLIDATED STATEMENTS OF CHANGES IN EQUITY - USD ($) $ in Millions	Total	Common Stock	Additional Paid-In Capital	Accumulated Other Comprehensive Income (Loss)	Retained Earnings	Treasury Stock at Cost	Non- controlling Interests
Beginning balance at Dec. 31, 2019	$ 3,499.1	$ 0.6	$ 707.2	$ (108.8)	$ 3,819.8	$ (1,481.3)	$ 561.6
Increase (Decrease) in Stockholders' Equity
Net income	231.2				86.3		144.9
Other comprehensive income (loss), net of tax	(53.5)			(46.1)			(7.4)
Share-based compensation	46.4		46.4
Common stock issued under share-based incentive plans	(6.5)		(40.9)			34.4
Share repurchases	(204)		0.1			(204.1)
Dividends	(16)				(16)
Affiliate equity activity:
Affiliate equity compensation	36.3		11.4				24.9
Issuances	19.9		1.1				18.8
Purchases	43.9		57.4				(13.5)
Changes in redemption value of Redeemable non-controlling interests	(18.6)		(18.6)
Transfers to Redeemable non-controlling interests	(5.6)						(5.6)
Capital contributions and other	4.9						4.9
Distributions to non-controlling interests	(249.1)						(249.1)
Ending balance at Sep. 30, 2020	3,328.4	0.6	764.1	(154.9)	3,890.1	(1,651)	479.5
Beginning balance at Jun. 30, 2020	3,341.9	0.6	768.2	(170.4)	3,819.3	(1,563)	487.2
Increase (Decrease) in Stockholders' Equity
Net income	127.8				71.3		56.5
Other comprehensive income (loss), net of tax	24.9			15.5			9.4
Share-based compensation	15.7		15.7
Common stock issued under share-based incentive plans	(0.1)		(1.1)			1
Share repurchases	(84.4)		4.6			(89)
Dividends	(0.5)				(0.5)
Affiliate equity activity:
Affiliate equity compensation	9.5		3.5				6
Issuances	3.1		2.9				0.2
Purchases	18.8		21				(2.2)
Changes in redemption value of Redeemable non-controlling interests	(50.7)		(50.7)
Transfers to Redeemable non-controlling interests	(0.2)						(0.2)
Distributions to non-controlling interests	(77.4)						(77.4)
Ending balance at Sep. 30, 2020	3,328.4	0.6	764.1	(154.9)	3,890.1	(1,651)	479.5
Beginning balance at Dec. 31, 2020	3,317.3	0.6	728.9	(98.3)	4,005.5	(1,857)	537.6
Increase (Decrease) in Stockholders' Equity
Net income	606.7				387.3		219.4
Other comprehensive income (loss), net of tax	10.7			14.6			(3.9)
Share-based compensation	44.5		44.5
Common stock issued under share-based incentive plans	(17.3)		(54.1)			36.8
Repurchases of junior convertible securities	(6.1)		(6.1)
Share repurchases	(390)		17.3			(407.3)
Dividends	(1.3)				(1.3)
Affiliate equity activity:
Affiliate equity compensation	46.1		9.6				36.5
Issuances	4.3		(16.7)				21
Purchases	22.7		9.5				13.2
Changes in redemption value of Redeemable non-controlling interests	(176.9)		(176.9)
Transfers to Redeemable non-controlling interests	(3.9)						(3.9)
Capital contributions and other	3.6						3.6
Distributions to non-controlling interests	(260.9)						(260.9)
Ending balance at Sep. 30, 2021	3,199.5	0.6	556	(83.7)	4,391.5	(2,227.5)	562.6
Beginning balance at Jun. 30, 2021	3,157.9	0.6	539.3	(64.8)	4,263.4	(2,128.9)	548.3
Increase (Decrease) in Stockholders' Equity
Net income	208.4				128.4		80
Other comprehensive income (loss), net of tax	(21.6)			(18.9)			(2.7)
Share-based compensation	21.2		21.2
Common stock issued under share-based incentive plans	(6.4)		(7.8)			1.4
Repurchases of junior convertible securities	(1.3)		(1.3)
Share repurchases	(100)					(100)
Dividends	(0.3)				(0.3)
Affiliate equity activity:
Affiliate equity compensation	11.4		2.5				8.9
Issuances	0.5						0.5
Purchases	(1.2)		1.2				(2.4)
Changes in redemption value of Redeemable non-controlling interests	0.9		0.9
Transfers to Redeemable non-controlling interests	(0.1)						(0.1)
Capital contributions and other	(2.5)						(2.5)
Distributions to non-controlling interests	(67.4)						(67.4)
Ending balance at Sep. 30, 2021	$ 3,199.5	$ 0.6	$ 556	$ (83.7)	$ 4,391.5	$ (2,227.5)	$ 562.6

CONSOLIDATED STATEMENTS OF CH_2

CONSOLIDATED STATEMENTS OF CHANGES IN EQUITY (Parenthetical) - $ / shares	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Statement of Stockholders' Equity [Abstract]
Dividends (in dollars per share)	$ 0.01	$ 0.01	$ 0.03	$ 0.34

CONSOLIDATED STATEMENTS OF CASH

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020
Cash flow from (used in) operating activities:
Net income	$ 606.7	$ 231.2
Adjustments to reconcile Net income to cash flow from (used in) operating activities:
Intangible amortization and impairments	25.3	133.4
Depreciation and other amortization	12.5	14.7
Deferred income tax expense	87.6	10.6
Equity method loss (income) (net)	(125.1)	78.8
Distributions of earnings received from equity method investments	288.1	197.2
Share-based compensation and Affiliate equity expense	90.9	82.7
Other non-cash items	(69.1)	20.3
Changes in assets and liabilities:
Purchases of securities by consolidated Affiliate sponsored investment products	(91.1)	(83.5)
Sales of securities by consolidated Affiliate sponsored investment products	49.9	77.6
Decrease (increase) in receivables	(81)	9
(Increase) decrease in other assets	22.5	(8.5)
(Decrease) increase in payables, accrued liabilities, and other liabilities	80.1	(136.7)
Cash flow from operating activities	897.3	626.8
Cash flow from (used in) investing activities:
Investments in Affiliates	(144.9)	(2.4)
Return of capital from equity method investments	3.4	0
Purchase of fixed assets	(4.9)	(6.8)
Purchase of investment securities	(57.4)	(35.7)
Sale of investment securities	26	36.9
Cash flow used in investing activities	(177.8)	(8)
Cash flow from (used in) financing activities:
Borrowings of senior bank debt, senior notes, and junior subordinated notes	200	874.8
Repayments of senior bank debt and junior convertible securities	(26.1)	(350)
Repurchases of common stock (net)	(493)	(213)
Dividends paid on common stock	(1.3)	(16.3)
Distributions to non-controlling interests	(260.9)	(249.1)
Affiliate equity (purchases) / issuances (net)	(47.8)	(232.5)
Other financing items	3.6	(35.4)
Cash flow used in financing activities	(625.5)	(221.5)
Effect of foreign currency exchange rate changes on cash and cash equivalents	(1.8)	(5.3)
Net increase in cash and cash equivalents	92.2	392
Cash and cash equivalents at beginning of period	1,039.7	539.6
.
Effect of deconsolidation of Affiliates and Affiliate sponsored investment products	(3.9)	(2.2)
Cash and cash equivalents at end of period	$ 1,128	$ 929.4

Basis of Presentation and Use o

Basis of Presentation and Use of Estimates	9 Months Ended
Basis of Presentation and Use of Estimates	Sep. 30, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Presentation and Use of Estimates	Basis of Presentation and Use of Estimates The Consolidated Financial Statements of Affiliated Managers Group, Inc. (the “Company”) have been prepared in accordance with accounting principles generally accepted in the U.S. (“GAAP”) for interim financial information and with the instructions to Form 10-Q and Rule 10-01 of Regulation S-X. Accordingly, they do not include all of the information and footnotes required by GAAP for full year financial statements. In the opinion of management, all normal and recurring adjustments considered necessary for a fair statement of the Company’s interim financial position and results of operations have been included and all intercompany balances and transactions have been eliminated. Certain reclassifications have been made to the prior period’s financial statements to conform to the current period’s presentation. Operating results for interim periods are not necessarily indicative of the results that may be expected for any other period or for the full year. The Company’s Annual Report on Form 10-K for the fiscal year ended December 31, 2020 includes additional information about its operations, financial position, and accounting policies, and should be read in conjunction with this Quarterly Report on Form 10-Q. The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts and disclosures in the financial statements. Actual results could differ from those estimates.

Accounting Standards and Polici

Accounting Standards and Policies	9 Months Ended
Accounting Standards and Policies	Sep. 30, 2021
Accounting Policies [Abstract]
Accounting Standards and Policies	Accounting Standards and Policies Recently Adopted Accounting Standards Effective January 1, 2021, the Company adopted Accounting Standard Update (“ASU”) 2019-12, Simplifying the Accounting for Income Taxes. The adoption of this standard did not have a significant impact on the Company’s Consolidated Financial Statements. Recent Accounting Developments In August 2020, the Financial Accounting Standards Board (“FASB”) issued ASU 2020-06, Debt with Conversion and Other Options and Derivatives and Hedging - Contracts in Entity’s Own Equity, which simplifies the accounting for convertible instruments and also modifies how particular convertible instruments and certain contracts that may be settled in cash or shares impact the diluted earnings per share calculation. The standard is effective for interim and annual periods beginning after December 15, 2021 for the Company and its consolidated Affiliates, and is effective for interim and annual periods beginning after December 15, 2023 for the Company’s Affiliates accounted for under the equity method. The Company’s adoption of ASU 2020-06 will result in the Company accounting for its convertible debt instrument as a single liability measured at amortized cost and will modify how certain equity instruments that may be settled in cash or shares, at the Company’s option, impact the calculation of Earnings per share (diluted). The Company plans to adopt the standard using a modified retrospective method. Assuming no further repurchases of its convertible debt instruments, the Company currently estimates the adoption of this standard will result in increases in Debt and beginning Retained Earnings of $102.4 million and $4.6 million, respectively, and decreases in Additional paid-in-capital and Deferred income tax liability (net) of $81.4 million and $25.6 million, respectively. While the potential dilution to the calculation of Earnings per share (diluted) could be material and depends upon a number of factors, such as current share price, number of convertible shares, and conversion price, if the standard was adopted in the current period, Earnings per share (diluted) would not be significantly impacted.

Investments in Marketable Secur

Investments in Marketable Securities	9 Months Ended
Investments in Marketable Securities	Sep. 30, 2021
Marketable Securities [Abstract]
Investments in Marketable Securities	Investments in Marketable Securities The following table summarizes the cost, gross unrealized gains, gross unrealized losses, and fair value of Investments in marketable securities: December 31, September 30, Cost $ 69.4 $ 68.5 Unrealized gains 5.5 8.2 Unrealized losses (0.0 ) (0.9) Fair value $ 74.9 $ 75.8 As of December 31, 2020 and September 30, 2021, Investments in marketable securities include consolidated Affiliate sponsored investment products with fair values of $52.3 million and $19.0 million, respectively.

Other Investments

Other Investments	9 Months Ended
Other Investments	Sep. 30, 2021
Investments, All Other Investments [Abstract]
Other Investments	Other Investments Other investments consist of investments in funds advised by the Company’s Affiliates that are carried at net asset value (“NAV”) as a practical expedient and investments without readily determinable fair values. The income or loss related to these investments is recorded in Investment and other income on the Consolidated Statements of Income. Investments Measured at NAV as a Practical Expedient The Company’s Affiliates sponsor investment products in which the Company and its consolidated Affiliates may make general partner and seed capital investments. The Company uses the NAV of these investments as a practical expedient for their fair values. The following table summarizes the fair value of these investments and any related unfunded commitments: December 31, 2020 September 30, 2021 Category of Investment Fair Value Unfunded Fair Value Unfunded Private equity funds (1) $ 235.4 $ 122.2 $ 307.0 $ 114.1 Investments in other strategies (2) 8.0 — 16.6 — Total (3) $ 243.4 $ 122.2 $ 323.6 $ 114.1 ___________________________ (1) The Company accounts for the majority of its interests in private equity funds under the equity method of accounting and uses NAV as a practical expedient, one quarter in arrears (adjusted for current period calls and distributions), to determine the fair value. These funds primarily invest in a broad range of third-party funds and direct investments. Distributions will be received as the underlying assets are liquidated over the life of the funds, which is generally up to 15 years. (2) These are multi-disciplinary funds that invest across various asset classes and strategies, including equity, credit, and real estate. Investments are generally redeemable on a daily, monthly, or quarterly basis. (3) Fair value attributable to the controlling interest was $164.4 million and $217.7 million as of December 31, 2020 and September 30, 2021, respectively. Investments Without Readily Determinable Fair Values The following table summarizes the cost, cumulative upward adjustments, and carrying amount of investments without readily determinable fair values: December 31, September 30, Cost $ 8.5 $ 8.5 Cumulative upward adjustments 5.3 25.0 Carrying amount $ 13.8 $ 33.5

Fair Value Measurements

Fair Value Measurements	9 Months Ended
Fair Value Measurements	Sep. 30, 2021
Fair Value Disclosures [Abstract]
Fair Value Measurements	Fair Value MeasurementsThe following tables summarize the Company’s financial assets and liabilities that are measured at fair value on a recurring basis: Fair Value Measurements December 31, Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Financial Assets Investments in marketable securities $ 74.9 $ 25.7 $ 49.2 $ — Derivative financial instruments (1) 3.5 — 3.5 — Financial Liabilities (2) Affiliate equity purchase obligations $ 22.0 $ — $ — $ 22.0 Derivative financial instruments 4.2 — 4.2 — Fair Value Measurements September 30, Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Financial Assets Investments in marketable securities $ 75.8 $ 61.1 $ 14.7 $ — Derivative financial instruments (1) 1.0 — 1.0 — Financial Liabilities (2) Affiliate equity purchase obligations $ 47.7 $ — $ — $ 47.7 Derivative financial instruments 2.5 — 2.5 — __________________________ (1) Amounts are presented within Other assets on the Consolidated Balance Sheets. (2) Amounts are presented within Other liabilities on the Consolidated Balance Sheets. Level 3 Financial Liabilities The following table presents the changes in level 3 liabilities for Affiliate equity purchase obligations: For the Three Months Ended September 30, For the Nine Months Ended September 30, 2020 2021 2020 2021 Balance, beginning of period $ 73.3 $ 47.9 $ 19.8 $ 22.0 Net realized and unrealized (gains) losses (1) (0.2) — (4.1) 2.2 Purchases and issuances (2) 85.8 3.3 292.8 86.3 Settlements and reductions (89.0) (3.5) (238.6) (62.8) Balance, end of period $ 69.9 $ 47.7 $ 69.9 $ 47.7 Net change in unrealized (gains) losses relating to instruments still held at the reporting date $ — $ — $ — $ — ___________________________ (1) Accretion expense for these arrangements and obligations is recorded in Interest expense in the Consolidated Statements of Income. (2) Includes transfers from Redeemable non-controlling interests. The following table presents certain quantitative information about the significant unobservable inputs used in valuing the Company’s level 3 fair value measurements: Quantitative Information About Level 3 Fair Value Measurements December 31, 2020 September 30, 2021 Valuation Unobservable Fair Value Range Weighted Average (1) Fair Value Range Weighted Average (1) Affiliate equity purchase obligations Discounted cash flow Growth rates (2) $ 22.0 (5)% - 8% 3 % $ 47.7 1% - 8% 5 % Discount rates 14% - 16% 15 % 15% - 17% 15 % ___________________________ (1) Calculated by comparing the relative fair value of an obligation to its respective total. (2) Represents growth rates of asset- and performance-based fees. Affiliate equity purchase obligations include agreements to purchase Affiliate equity. As of September 30, 2021, there were no changes to growth or discount rates that had a significant impact to Affiliate equity purchase obligations recorded in prior periods. Other Financial Assets and Liabilities Not Carried at Fair Value The Company has other financial assets and liabilities that are not required to be carried at fair value, but are required to be disclosed at fair value. The carrying amount of Cash and cash equivalents, Receivables, and Payables and accrued liabilities approximates fair value because of the short-term nature of these instruments. The carrying value of notes receivable, which is reported in Other assets, approximates fair value because interest rates and other terms are at market rates. The carrying value of the credit facilities approximates fair value because the credit facilities have variable interest based on selected short-term rates. The following table summarizes the Company’s other financial liabilities not carried at fair value: December 31, 2020 September 30, 2021 Carrying Value Fair Value Carrying Value Fair Value Fair Value Hierarchy Senior notes $ 1,097.3 $ 1,206.6 $ 1,097.8 $ 1,180.7 Level 2 Junior subordinated notes 565.7 623.1 765.8 804.3 Level 2 Junior convertible securities 318.4 427.6 301.4 457.7 Level 2

Investments in Affiliates and A

Investments in Affiliates and Affiliate Sponsored Investment Products	9 Months Ended
	Sep. 30, 2021
Variable Interest Entities
Investments in Affiliates and Affiliate Sponsored Investment Products	Investments in Affiliates and Affiliate Sponsored Investment Products In evaluating whether an investment must be consolidated, the Company evaluates the risk, rewards, and significant terms of each of its Affiliates and other investments to determine if an investment is considered a voting rights entity (“VRE”) or a variable interest entity (“VIE”). An entity is a VRE when the total equity investment at risk is sufficient to enable the entity to finance its activities independently, and when the equity holders have the obligation to absorb losses, the right to receive residual returns, and the right to direct the activities of the entity that most significantly impact its economic performance. An entity is a VIE when it lacks one or more of the characteristics of a VRE, which, for the Company, are Affiliate investments structured as partnerships (or similar entities) where the Company is a limited partner and lacks substantive kick-out or substantive participation rights over the general partner. Assessing whether an entity is a VRE or VIE involves judgment. Upon the occurrence of certain events, management reviews and reconsiders its previous conclusion regarding the status of an entity as a VRE or a VIE. The Company consolidates VREs when it has control over significant operating, financial, and investing decisions of the entity. When the Company lacks such control, but is deemed to have significant influence, the Company accounts for the VRE under the equity method. Other investments with readily determinable fair values in which the Company does not have rights to exercise significant influence are recorded at fair value on the Consolidated Balance Sheets, with changes in fair value included in Investment and other income. The Company consolidates VIEs when it is the primary beneficiary of the entity, which is defined as having the power to direct the activities that most significantly impact the VIE’s economic performance and the obligation to absorb losses of, or the right to receive benefits from, the entity that could potentially be significant to the VIE. Substantially all of the Company’s consolidated Affiliates considered VIEs are controlled because the Company holds a majority of the voting interests or it is the managing member or general partner. Furthermore, an Affiliate’s assets can be used for purposes other than the settlement of the respective Affiliate’s obligations. The Company applies the equity method of accounting to VIEs where the Company is not the primary beneficiary, but has the ability to exercise significant influence over operating and financial matters of the VIE. Investments in Affiliates Substantially all of the Company’s Affiliates are considered VIEs and are either consolidated or accounted for under the equity method. A limited number of the Company’s Affiliates are considered VREs and most of these are accounted for under the equity method. When an Affiliate is consolidated, the portion of the earnings attributable to Affiliate management’s equity ownership is included in Net income (non-controlling interests) in the Consolidated Statements of Income. Undistributed earnings attributable to Affiliate managements’ equity ownership, along with their share of any tangible or intangible net assets, are presented within Non-controlling interests on the Consolidated Balance Sheets. Affiliate equity interests where the holder has certain rights to demand settlement are presented, at their current redemption values, as Redeemable non-controlling interests on the Consolidated Balance Sheets. The Company periodically issues, sells, and purchases the equity of its consolidated Affiliates. Because these transactions take place between entities that are under common control, any gains or losses attributable to these transactions are required to be included in Additional paid-in capital in the Consolidated Balance Sheets, net of any related income tax effects in the period the transaction occurs. When an Affiliate is accounted for under the equity method, the Company’s share of an Affiliate’s earnings or losses, net of amortization and impairments, is included in Equity method income (loss) (net) in the Consolidated Statements of Income and the carrying value of the Affiliate is reported in Equity method investments in Affiliates (net) in the Consolidated Balance Sheets. Deferred taxes recorded on intangible assets upon acquisition of an Affiliate accounted for under the equity method are presented on a gross basis within Equity method investments in Affiliates (net) and Deferred income tax liability (net) in the Consolidated Balance Sheets. The Company’s share of income taxes incurred directly by Affiliates accounted for under the equity method is recorded in Income tax expense in the Consolidated Statements of Income. The Company periodically performs assessments to determine if the fair value of an investment may have declined below its related carrying value for its Affiliates accounted for under the equity method for a period that the Company considers to be other-than-temporary. Where the Company believes that such declines may have occurred, the Company determines the amount of impairment using valuation methods, such as discounted cash flow analyses. Impairments are recorded as an expense in Equity method income (loss) (net) to reduce the carrying value of the Affiliate to its fair value. The unconsolidated assets, net of liabilities and non-controlling interests of Affiliates accounted for under the equity method considered VIEs, and the Company’s carrying value and maximum exposure to loss, were as follows: December 31, 2020 September 30, 2021 Unconsolidated Carrying Value and Unconsolidated Carrying Value and Affiliates accounted for under the equity method $ 1,384.2 $ 1,962.1 $ 1,194.6 $ 1,976.7 As of December 31, 2020 and September 30, 2021, the carrying value and maximum exposure to loss for all of the Company’s Affiliates accounted for under the equity method was $2,074.8 million and $2,085.2 million, respectively, including Affiliates accounted for under the equity method considered VREs of $112.7 million and $108.5 million, respectively. Affiliate Sponsored Investment Products The Company’s Affiliates sponsor various investment products where the Affiliate also acts as the investment adviser. These investment products are typically owned primarily by third-party investors; however, certain products are funded with general partner and seed capital investments from the Company and its Affiliates. Third-party investors in Affiliate sponsored investment products are generally entitled to substantially all of the economics of these products, except for the asset- and performance-based fees earned by the Company’s Affiliates or any gains or losses attributable to the Company’s or its Affiliates’ investments in these products. As a result, the Company generally does not consolidate these products unless the Company’s or its consolidated Affiliate’s interest in the product is considered substantial. When the Company’s or its consolidated Affiliates’ interests are considered substantial and the products are consolidated, the Company retains the specialized investment company accounting principles of the underlying products, and all of the underlying investments are carried at fair value in Investments in marketable securities in the Consolidated Balance Sheets, with corresponding changes in the investments’ fair values included in Investment and other income. Purchases and sales of securities are presented within purchases and sales by consolidated Affiliate sponsored investment products in the Consolidated Statements of Cash Flows, respectively, and the third-party investors’ interests are recorded in Redeemable non-controlling interests. When the Company or its consolidated Affiliates no longer control these products, due to a reduction in ownership or other reasons, the products are deconsolidated with only the Company’s or its consolidated Affiliate’s investment in the product reported from the date of deconsolidation. The Company’s carrying value, and maximum exposure to loss from unconsolidated Affiliate sponsored investment products, is its or its consolidated Affiliates’ interests in the unconsolidated net assets of the respective products. The net assets of unconsolidated VIEs attributable to Affiliate sponsored investment products, and the Company’s carrying value and maximum exposure to loss, were as follows: December 31, 2020 September 30, 2021 Unconsolidated Carrying Value and Unconsolidated Carrying Value and Affiliate sponsored investment products $ 2,378.2 $ 0.9 $ 3,155.9 $ 13.6

Debt

Debt	9 Months Ended
Debt	Sep. 30, 2021
Debt Disclosure [Abstract]
Debt	Debt The following table summarizes the Company’s Debt: December 31, September 30, Senior bank debt $ 349.8 $ 349.8 Senior notes 1,091.9 1,093.1 Junior subordinated notes 556.4 751.4 Junior convertible securities 314.0 297.5 Debt $ 2,312.1 $ 2,491.8 The Company’s senior notes, junior subordinated notes, and junior convertible securities are carried at amortized cost. Unamortized discounts and debt issuance costs are presented within the Consolidated Balance Sheets as an adjustment to the carrying value of the associated debt. Senior Bank Debt The Company has a $1.25 billion senior unsecured multicurrency revolving credit facility (the “revolver”) and a $350.0 million senior unsecured term loan facility (the “term loan” and, together with the revolver, the “credit facilities”). The Company amended and restated the revolver in October 2021, extending the maturity from January 18, 2024 to October 23, 2026, and amended the term loan in January 2021 and June 2021, and further amended and restated the term loan in October 2021, extending the maturity from January 18, 2023 to October 23, 2026. Through these amendments, the Company also reduced applicable rates for the revolver and the term loan, and provided for customary LIBOR succession provisions. The commercial terms of the revolver and the term loan otherwise remain the same. Subject to certain conditions, the Company may increase the commitments under the revolver by up to an additional $500.0 million and may borrow up to an additional $75.0 million under the term loan. The Company pays interest on any outstanding obligations under the credit facilities at specified rates, currently based either on an applicable LIBOR or prime rate, plus a marginal rate determined based on its credit rating. As of September 30, 2021, the interest rate for the Company’s borrowings under the term loan was LIBOR plus 0.85%. As of December 31, 2020 and September 30, 2021, the Company had no outstanding borrowings under the revolver. Senior Notes As of September 30, 2021, the Company had senior notes outstanding. The carrying value of the senior notes is accreted to the principal amount at maturity over the remaining life of the underlying instrument. The principal terms of the senior notes outstanding as of September 30, 2021 were as follows: 2024 2025 2030 Issue date February 2014 February 2015 June 2020 Maturity date February 2024 August 2025 June 2030 Par value (in millions) $ 400.0 $ 350.0 $ 350.0 Stated coupon 4.25 % 3.50 % 3.30 % Coupon frequency Semi-annually Semi-annually Semi-annually Potential call date Any time Any time Any time Call price As defined As defined As defined The senior notes may be redeemed, in whole or in part, at any time, in the case of the 2024 and 2025 senior notes, and at any time prior to March 15, 2030, in the case of the 2030 senior notes. In each case, the senior notes may be redeemed at a make-whole redemption price, plus accrued and unpaid interest. The make-whole redemption price, in each case, is equal to the greater of 100% of the principal amount of the notes to be redeemed and the remaining principal and interest payments on the notes being redeemed (excluding accrued but unpaid interest to, but not including, the redemption date) discounted to their present value as of the redemption date at the applicable treasury rate plus 0.25%, in the case of the 2024 and the 2025 senior notes, and to their present value as of the redemption date on a semi-annual basis at the applicable treasury rate plus 0.40%, in the case of the 2030 senior notes. Junior Subordinated Notes As of September 30, 2021, the Company had junior subordinated notes outstanding. The carrying value of the junior subordinated notes is accreted to the principal amount at maturity over the remaining life of the underlying instrument. The principal terms of the junior subordinated notes outstanding as of September 30, 2021 were as follows: 2059 2060 2061 Issue date March 2019 September 2020 July 2021 Maturity date March 2059 September 2060 September 2061 Par value (in millions) $ 300.0 $ 275.0 $ 200.0 Stated coupon 5.875 % 4.75 % 4.20 % Coupon frequency Quarterly Quarterly Quarterly Potential call date March 2024 September 2025 September 2026 Call price As defined As defined As defined Listing NYSE NYSE NYSE The junior subordinated notes may be redeemed at any time, in whole or in part, on or after March 30, 2024, in the case of the 2059 junior subordinated notes, on or after September 30, 2025, in the case of the 2060 junior subordinated notes, and on or after September 30, 2026, in the case of the 2061 junior subordinated notes. In each case, the junior subordinated notes may be redeemed at 100% of the principal amount of the notes being redeemed, plus any accrued and unpaid interest thereon. Prior to the applicable redemption date, at the Company’s option, the applicable junior subordinated notes may also be redeemed, in whole but not in part, at 100% of the principal amount, plus any accrued and unpaid interest, if certain changes in tax laws, regulations, or interpretations occur; or at 102% of the principal amount, plus any accrued and unpaid interest, if a rating agency makes certain changes relating to the equity credit criteria for securities with features similar to the applicable notes. The Company may, at its option, and subject to certain conditions and restrictions, defer interest payments subject to the terms of the junior subordinated notes. Junior Convertible Securities As of September 30, 2021, the Company had 5.15% junior convertible trust preferred securities outstanding (the “junior convertible securities”) with a carrying value of $301.4 million. The carrying value is accreted to the principal amount at

Derivative Financial Instrument

Derivative Financial Instruments	9 Months Ended
Derivative Financial Instruments	Sep. 30, 2021
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative Financial Instruments	Derivative Financial Instruments The Company and its Affiliates may use derivative financial instruments to offset exposure to changes in interest rates, foreign currency exchange rates, and markets. In the first quarter of 2020, the Company terminated its pound sterling-denominated forward foreign currency contracts and its corresponding collar contracts, which were designated as net investment hedges, and upon settlement, the Company received net proceeds of $24.9 million. The net proceeds from the termination of the contracts are presented within sale of investment securities in the Consolidated Statements of Cash Flows. The Company has an interest rate swap contract (the “interest rate swap”) with a large financial institution (the “swap counterparty”), which will expire in March 2023. The interest rate swap, which is designated as a cash flow hedge, is used to exchange a portion of the Company’s LIBOR-based interest payments for fixed-rate interest payments. Under the contract, the Company receives payments based on one month LIBOR and makes payments based on an annual fixed-rate of 0.5135% on a notional amount of $250.0 million. The terms of the contract also require the Company and the swap counterparty to post cash collateral in certain circumstances throughout the duration of the contract. As of September 30, 2021, the Company held no cash collateral from the swap counterparty, and the swap counterparty held $1.1 million of cash collateral from the Company. Certain of the Company’s Affiliates use forward foreign currency contracts to hedge the risk of foreign exchange rate movements, which are designated as cash flow hedges. The Company assesses hedge effectiveness on a quarterly basis. For derivative financial instruments designated as cash flow hedges, the Company uses a qualitative method of assessing hedge effectiveness by comparing the notional amounts, timing of payments, currencies (for the forward foreign currency contracts), and interest rates (for the interest rate swap). Upon termination of these instruments or the repayment of the Company’s outstanding LIBOR-based borrowings, any gain or loss recorded in Accumulated other comprehensive loss in the Consolidated Balance Sheets will be reclassified into earnings. Changes in the fair values of cash flow hedges are reported in Change in net realized and unrealized gain (loss) on derivative financial instruments in the Consolidated Statements of Comprehensive Income. Changes in the fair values of the effective net investment hedges are reported in Foreign currency translation gain (loss) in the Consolidated Statements of Comprehensive Income. Upon the sale or liquidation of the underlying investment, any gain or loss remaining in Accumulated other comprehensive loss will be reclassified to earnings. The following table summarizes the Company’s and its Affiliates’ derivative financial instruments measured at fair value on a recurring basis: December 31, 2020 September 30, 2021 Assets Liabilities Assets Liabilities Forward foreign currency contracts $ 3.5 $ (2.3) $ 1.0 $ (1.4) Interest rate swap — (1.9) — (1.1) Total $ 3.5 $ (4.2) $ 1.0 $ (2.5) The Company and certain of its consolidated Affiliates have entered into contracts that do not include set-off rights and are therefore presented on a gross basis in Other assets and Other liabilities; they were $3.5 million and $4.2 million, respectively, as of December 31, 2020, and $1.0 million and $2.5 million, respectively, as of September 30, 2021. The following table summarizes the effects of derivative financial instruments on the Consolidated Statements of Comprehensive Income and the Consolidated Statements of Income: For the Three Months Ended September 30, 2020 2021 Gain (Loss) Recognized in Other Comprehensive Income Gain Reclassified from Accumulated Other Comprehensive Loss into Earnings Gain (Loss) Recognized in Earnings from Excluded Components (1) Gain (Loss) Recognized in Other Comprehensive Income Gain Reclassified from Accumulated Other Comprehensive Loss into Earnings Gain (Loss) Recognized in Earnings from Excluded Components (1) Forward foreign currency contracts $ 0.4 $ 0.1 $ — $ (2.0) $ 0.4 $ — Interest rate swap (0.1) — — 0.1 — — Total $ 0.3 $ 0.1 $ — $ (1.9) $ 0.4 $ — For the Nine Months Ended September 30, 2020 2021 Gain (Loss) Recognized in Other Comprehensive Loss Gain Reclassified from Accumulated Other Comprehensive Loss into Earnings Gain Recognized in Earnings from Excluded Components (1) Gain (Loss) Recognized in Other Comprehensive Income Gain Reclassified from Accumulated Other Comprehensive Loss into Earnings Gain (Loss) Recognized in Earnings from Excluded Components (1) Forward foreign currency contracts $ 64.9 $ 0.4 $ 2.8 $ (1.6) $ 1.4 $ — Put options (47.7) — — — — — Call options (1.3) — — — — — Interest rate swap (2.1) — — 0.7 — — Total $ 13.8 $ 0.4 $ 2.8 $ (0.9) $ 1.4 $ — ___________________________ (1) The excluded components of the forward foreign currency contracts were recognized in earnings on a straight-line basis over the respective period of the contracts as a reduction to Interest expense.

Commitments and Contingencies

Commitments and Contingencies	9 Months Ended
Commitments and Contingencies	Sep. 30, 2021
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies From time to time, the Company and its Affiliates may be subject to claims, legal proceedings, and other contingencies in the ordinary course of their business activities. Any such matters are subject to various uncertainties, and it is possible that some of these matters may be resolved in a manner unfavorable to the Company or its Affiliates. The Company and its Affiliates establish accruals, as necessary, for matters for which the outcome is probable and the amount of the liability can be reasonably estimated. The Company has committed to co-invest in certain Affiliate sponsored investment products. As of September 30, 2021, these unfunded commitments were $114.1 million and may be called in future periods. As of September 30, 2021, the Company was contingently liable to make payments of $188.0 million related to the achievement of specified financial targets by certain of its Affiliates accounted for under the equity method, of which $40.5 million may become payable in 2022 and $147.5 million may become payable from 2023 through 2029. As of September 30, 2021, the Company expected to make payments of approximately $15 million. In the event certain financial targets are not met at one of the Company’s Affiliates, the Company may receive payments of up to $12.5 million and also has the option to reduce its ownership interest and receive an incremental payment of $25.0 million. Affiliate equity interests provide holders at consolidated Affiliates with a conditional right to put their interests to the Company over time. See Note 15. In connection with one of the Company’s investments in an Affiliate accounted for under the equity method, a minority owner has the right to elect to sell a portion of its ownership interest in the Affiliate to the Company annually. If the minority owner sells its interest to the Company, the Company will continue to account for the Affiliate under the equity method. In the fourth quarter of 2020, the Company was notified by the minority owner that it may elect to sell a 5% interest in the Affiliate to the Company. In the first quarter of 2021, with the consent of the Company, the minority owner rescinded this notice. As of September 30, 2021, the minority owner maintained a 14% ownership interest in the Affiliate. The Company and certain of its consolidated Affiliates operate under regulatory authorities that require the maintenance of minimum financial or capital requirements. The Company’s management is not aware of any significant violations of such requirements. On July 2, 2021, the Company entered into a definitive agreement to acquire a majority equity interest in Parnassus Investments, an ESG-dedicated fund manager. On October 1, 2021, the Company completed its investment for upfront cash consideration of $300.4 million, deferred consideration of $150.2 million which is payable in the fourth quarter of 2022, and a contingent payment obligation related to the achievement of specified financial targets of up to $75.1 million which may become payable from 2024 through 2026. This transaction was financed with available cash.

Goodwill and Acquired Client Re

Goodwill and Acquired Client Relationships	9 Months Ended
Goodwill and Acquired Client Relationships	Sep. 30, 2021
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill and Acquired Client Relationships	Goodwill and Acquired Client Relationships The following tables present the changes in the Company’s consolidated Affiliates’ Goodwill and components of Acquired client relationships (net): Goodwill Balance, as of December 31, 2020 $ 2,661.4 Foreign currency translation (2.9) Balance, as of September 30, 2021 $ 2,658.5 As of September 30, 2021, the Company completed its annual impairment assessment on goodwill and no impairment was indicated. Acquired Client Relationships (Net) Definite-lived Indefinite-lived Total Gross Book Accumulated Net Book Net Book Net Book Balance, as of December 31, 2020 $ 1,166.6 $ (1,026.8) $ 139.8 $ 909.0 $ 1,048.8 Intangible amortization and impairments — (25.3) (25.3) — (25.3) Foreign currency translation (0.2) 0.1 (0.1) (5.2) (5.3) Balance, as of September 30, 2021 $ 1,166.4 $ (1,052.0) $ 114.4 $ 903.8 $ 1,018.2 Definite-lived acquired client relationships at the Company’s consolidated Affiliates are amortized over their expected period of economic benefit. The Company recorded amortization expense within Intangible amortization and impairments in the Consolidated Statements of Income for these relationships of $7.0 million and $48.2 million for the three and nine months ended September 30, 2020, respectively, and $8.9 million and $25.3 million for the three and nine months ended September 30, 2021, respectively. Based on relationships existing as of September 30, 2021, the Company estimates that its consolidated amortization expense will be approximately $9 million for the remainder of 2021, approximately $30 million in each of 2022 and 2023, approximately $15 million in 2024, and approximately $10 million in each of 2025 and 2026. In the second quarter of 2020, the Company agreed with a consolidated Affiliate to strategically reposition their business and to sell its equity interest in the Affiliate. The Company recorded an expense in Intangible amortization and impairments of $32.8 million attributable to the controlling interest ($60.3 million in aggregate) to reduce the carrying value of the Affiliate’s acquired client relationships to zero as of June 30, 2020. In the third quarter of 2020, the Company sold its interest in the Affiliate. In the third quarter of 2020, the Company completed an impairment assessment of the indefinite-lived acquired client relationships at one of its Affiliates, and determined that the fair value of the asset had declined below its carrying value. Accordingly, the Company recorded an expense in Intangible amortization and impairments of $12.5 million attributable to the controlling interest ($14.0 million in aggregate) to reduce the carrying value of the asset to fair value. The decline in the fair value was a result of a projected decline in assets under management that decreased the forecasted revenue associated with the asset. The fair value of the asset was determined using a discounted cash flow analysis, a level 3 fair value measurement that included a projected growth rate of (14)% for assets under management, a discount rate of 15% for asset-based fees, and a market participant tax rate of 25%. In addition, in the third quarter of 2020, the Company recorded an expense in Intangible amortization and impairments of $7.4 million attributable to the controlling interest ($10.9 million in aggregate) to reduce the carrying value of an indefinite-lived acquired client relationship to zero due to the closure of one of its Affiliate’s retail investment products. As of September 30, 2021, no impairments of indefinite-lived acquired client relationships were indicated. If financial markets become depressed for a prolonged period as a result of the novel coronavirus global pandemic (“COVID-19”) or other factors, the fair values of these assets could drop below their carrying values resulting in future impairments.

Equity Method Investments in Af

Equity Method Investments in Affiliates	9 Months Ended
Equity Method Investments in Affiliates	Sep. 30, 2021
Equity Method Investments and Joint Ventures [Abstract]
Equity Method Investments in Affiliates	Equity Method Investments in Affiliates In the first and second quarters of 2021, the Company completed minority investments in Boston Common Asset Management LLC (“Boston Common”) and OCP Asia Limited (“OCP Asia”), respectively. The majority of the consideration paid for both Boston Common and OCP Asia is deductible for U.S. tax purposes over a 15-year life. The Company’s purchase price allocation for each investment was measured using financial models that included assumptions of expected market performance, net client cash flows, and discount rates. The financial results of certain Affiliates accounted for under the equity method are recognized in the Consolidated Financial Statements one quarter in arrears. The following table presents the change in Equity method investments in Affiliates (net): Equity Method Investments in Affiliates (Net) Balance, as of December 31, 2020 $ 2,074.8 Investments in Affiliates 144.3 Earnings 218.9 Intangible amortization and impairments (93.8) Distributions of earnings (288.1) Return of capital (3.4) Foreign currency translation 25.8 Other 6.7 Balance, as of September 30, 2021 $ 2,085.2 Definite-lived acquired client relationships at the Company’s Affiliates accounted for under the equity method are amortized over their expected period of economic benefit. The Company recognized amortization expense for these relationships of $34.3 million and $110.5 million for the three and nine months ended September 30, 2020, respectively, and $29.3 million and $93.8 million for the three and nine months ended September 30, 2021, respectively. Based on relationships existing as of September 30, 2021, the Company estimates the amortization expense attributable to its Affiliates will be approximately $30 million for the remainder of 2021, approximately $80 million in each of 2022 and 2023, and approximately $50 million in each of 2024, 2025, and 2026. In the first quarter of 2020, the Company recorded a $140.0 million expense to reduce the carrying value of an Affiliate to fair value. The decline in the fair value was a result of a decline in assets under management and a reduction in projected growth, which decreased the forecasted revenue associated with the investment. The fair value of the investment was determined using a probability-weighted discounted cash flow analysis, a level 3 fair value measurement, that included projected compounded growth in assets under management over the first five years of (2)%, discount rates of 11% and 20% for asset- and performance-based fees, respectively, and a market participant tax rate of 25%. Based on the discounted cash flow analysis, the Company concluded that the fair value of its investment had declined below its carrying value and that the decline was other-than-temporary. As of September 30, 2021, the estimated fair values of the Company’s Affiliates accounted for under the equity method exceeded their carrying values. If financial markets become depressed for a prolonged period as a result of COVID-19 or other factors, or the financial performance of an Affiliate worsens as a result of net client cash outflows or performance, regardless of the performance of financial markets, the fair values of these assets could drop below their carrying values for periods considered other-than-temporary, resulting in future impairments. As of September 30, 2021, the Company was obligated to make deferred and contingent payments of $103.9 million related to certain of its Affiliates accounted for under the equity method, of which $63.9 million is payable in 2021, although this amount may be funded in future periods, and $40.0 million is payable in 2022.

Related Party Transactions

Related Party Transactions	9 Months Ended
Related Party Transactions	Sep. 30, 2021
Related Party Transactions [Abstract]
Related Party Transactions	Related Party Transactions A prior owner of one of the Company’s consolidated Affiliates retains interests in certain of the Affiliate’s private equity partnerships and, as a result, is a related party of the Company. The prior owner’s interests are presented within Other liabilities and were $35.4 million and $31.7 million as of December 31, 2020 and September 30, 2021, respectively. The Company may invest from time to time in funds or products advised by its Affiliates. The Company’s executive officers and directors may invest from time to time in funds advised or products offered by its Affiliates on substantially the same terms as other investors. In addition, the Company and its Affiliates earn asset- and performance-based fees and incur distribution and other expenses for services provided to Affiliate sponsored investment products. Affiliate management owners and the Company’s officers may serve as trustees or directors of certain investment vehicles from which the Company or an Affiliate earns fees.

Share-Based Compensation

Share-Based Compensation	9 Months Ended
Share-Based Compensation	Sep. 30, 2021
Share-based Payment Arrangement [Abstract]
Share-Based Compensation	Share-Based Compensation The following table presents share-based compensation expense: For the Three Months Ended September 30, For the Nine Months Ended September 30, 2020 2021 2020 2021 Share-based compensation $ 15.7 $ 21.2 $ 46.4 $ 44.5 Tax benefit 2.9 3.5 8.4 7.8 As of December 31, 2020, the Company had unrecognized share-based compensation expense of $86.2 million. As of September 30, 2021, the Company had unrecognized share-based compensation expense of $82.5 million, which will be recognized over a weighted average period of approximately three years (assuming no forfeitures). Restricted Stock The following table summarizes transactions in the Company’s restricted stock units: Restricted Stock Units Weighted Average Grant Date Value Unvested units - December 31, 2020 1.2 $ 99.46 Units granted 0.2 139.71 Units vested (0.3) 130.58 Units forfeited (0.1) 105.45 Performance condition changes 0.1 80.19 Unvested units - September 30, 2021 1.1 94.22 For the nine months ended September 30, 2020 and 2021, the Company granted restricted stock units with fair values of $31.6 million and $27.8 million, respectively. These restricted stock units were valued based on the closing price of the Company’s common stock on the grant date and the number of shares expected to vest. Restricted stock units containing vesting conditions generally require service over a period of three years to four years and may also require the satisfaction of certain performance conditions. For awards with performance conditions, the number of restricted stock units expected to vest may change over time depending upon the performance level achieved. Stock Options The following table summarizes transactions in the Company’s stock options: Stock Options Weighted Average Weighted Average Unexercised options outstanding - December 31, 2020 2.9 $ 82.14 Options granted 0.0 150.68 Options exercised (0.2) 120.12 Options forfeited (0.0 ) 154.44 Performance condition changes 0.6 74.42 Unexercised options outstanding - September 30, 2021 3.3 78.21 4.8 Exercisable at September 30, 2021 0.2 131.74 1.6 For the nine months ended September 30, 2020 and 2021, the Company granted stock options with fair values of $4.4 million and $2.0 million, respectively. Stock options generally vest over a period of three years to five years and expire seven years after the grant date. All stock options have been granted with exercise prices equal to the closing price of the Company’s common stock on the grant date. Substantially all of the Company’s outstanding stock options contain both service and performance conditions. For awards with performance conditions, the number of stock options expected to vest may change over time depending upon the performance level achieved. The weighted average fair value of options granted was $18.23 and $54.19, per option, for the nine months ended September 30, 2020 and 2021, respectively. The Company uses the Black-Scholes option pricing model to determine the fair value of options. The weighted average grant date assumptions used to estimate the fair value of stock options granted were as follows: For the Nine Months Ended September 30, 2020 2021 Dividend yield 1.6 % 0.0 % Expected volatility 30.4 % 37.1 % Risk-free interest rate 0.9 % 1.0 % Expected life of options (in years) 5.7 5.7 Forfeiture rate — % — %

Redeemable Non-Controlling Inte

Redeemable Non-Controlling Interests	9 Months Ended
Redeemable Non-Controlling Interests	Sep. 30, 2021
Noncontrolling Interest [Abstract]
Redeemable Non-Controlling Interests	Redeemable Non-Controlling Interests Affiliate equity interests provide holders with an equity interest in one of the Company’s Affiliates, consistent with the structured partnership interests in place at the respective Affiliate. Affiliate equity holders generally have a conditional right to put their interests to the Company at certain intervals (between five years and 15 years from the date the equity interest is received by the Affiliate equity holder or on an annual basis following an Affiliate equity holder’s departure). Prior to becoming redeemable, the Company’s Affiliate equity is presented within Non-controlling interests. Upon becoming redeemable, these interests are reclassified to Redeemable non-controlling interests at their current redemption values. Changes in the current redemption value are recorded to Additional paid-in capital. When the Company receives a put notice and, therefore, has an unconditional obligation to purchase Affiliate equity interests, the interests are reclassified from Redeemable non-controlling interests to Other liabilities. The following table presents the changes in Redeemable non-controlling interests: Redeemable Non-controlling Interests Balance, as of December 31, 2020 (1) $ 671.5 Decrease attributable to consolidated Affiliate sponsored investment products (17.1) Transfers to Other liabilities (86.3) Transfers from Non-controlling interests 3.9 Changes in redemption value 176.9 Balance, as of September 30, 2021 (1) $ 748.9 ___________________________ (1) As of December 31, 2020 and September 30, 2021, Redeemable non-controlling interests include consolidated Affiliate sponsored investment products primarily attributable to third-party investors of $35.4 million and $18.3 million, respectively.

Affiliate Equity

Affiliate Equity	9 Months Ended
Affiliate Equity	Sep. 30, 2021
Affiliate Equity [Abstract]
Affiliate Equity	Affiliate Equity Affiliate equity interests are allocated income in a manner that is consistent with the structured partnership interests in place at the respective Affiliate. The Company’s Affiliates generally pay quarterly distributions to Affiliate equity holders. Distributions paid to non-controlling interest Affiliate equity holders were $249.1 million and $260.9 million, for the nine months ended September 30, 2020 and 2021, respectively. The Company periodically purchases Affiliate equity from and issues Affiliate equity to the Company’s consolidated Affiliate partners and its officers under agreements that provide the Company a conditional right to call and Affiliate equity holders the conditional right to put their Affiliate equity interests to the Company at certain intervals. For Affiliates accounted for under the equity method, the Company does not typically have such put and call arrangements. For the nine months ended September 30, 2020 and 2021, the amount of cash paid for purchases was $249.6 million and $65.9 million, respectively. For the nine months ended September 30, 2020 and 2021, the total amount of cash received for issuances was $17.1 million and $18.1 million, respectively. Sales and purchases of Affiliate equity generally occur at fair value; however, the Company also grants Affiliate equity to its consolidated Affiliate partners and its officers as a form of compensation. If the equity is issued for consideration below the fair value of the equity, or purchased for consideration above the fair value of the equity, the difference is recorded as compensation expense in Compensation and related expenses in the Consolidated Statements of Income over the requisite service period. The following table presents Affiliate equity compensation expense: For the Three Months Ended September 30, For the Nine Months Ended September 30, 2020 2021 2020 2021 Controlling interest $ 3.5 $ 2.8 $ 11.4 $ 9.9 Non-controlling interests 6.0 8.9 24.9 36.5 Total $ 9.5 $ 11.7 $ 36.3 $ 46.4 The following table presents unrecognized Affiliate equity compensation expense: Controlling Interest Remaining Life Non-controlling Interests Remaining Life December 31, 2020 $ 35.9 4 years $ 109.7 5 years September 30, 2021 47.6 5 years 108.1 4 years The Company records amounts receivable from, and payable to, Affiliate equity holders in connection with the transfer of Affiliate equity interests that have not settled at the end of the period. The total receivable was $9.6 million and $15.5 million as of December 31, 2020 and September 30, 2021, respectively, and was included in Other assets. The total payable was $22.0 million and $47.7 million as of December 31, 2020 and September 30, 2021, respectively, and was included in Other liabilities. Effects of Changes in the Company’s Ownership in Affiliates The Company periodically acquires interests from, and transfers interests to, Affiliate equity holders. Because these transactions do not result in a change of control, any gain or loss related to these transactions is recorded to Additional paid-in capital, which increases or decreases the controlling interest’s equity. No gain or loss related to these transactions is recognized in the Consolidated Statements of Income or the Consolidated Statements of Comprehensive Income. While the Company presents the current redemption value of Affiliate equity within Redeemable non-controlling interests, with changes in the current redemption value increasing or decreasing the controlling interest’s equity over time, the following table presents the cumulative effect that ownership changes had on the controlling interest’s equity related only to Affiliate equity transactions that settled during the applicable periods: For the Three Months Ended September 30, For the Nine Months Ended September 30, 2020 2021 2020 2021 Net income (controlling interest) $ 71.3 $ 128.4 $ 86.3 $ 387.3 Increase (decrease) in controlling interest paid-in capital from Affiliate equity issuances 2.9 — 1.6 (17.5) Decrease in controlling interest paid-in capital from Affiliate equity purchases (65.4) (1.2) (226.0) (57.2) Net income (loss) (controlling interest) including the net impact of Affiliate equity transactions $ 8.8 $ 127.2 $ (138.1) $ 312.6

Income Taxes

Income Taxes	9 Months Ended
Income Taxes	Sep. 30, 2021
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes The Company’s consolidated income tax provision includes taxes attributable to the controlling interest and, to a lesser extent, taxes attributable to the non-controlling interests. The following table presents the consolidated provision for income taxes: For the Three Months Ended September 30, For the Nine Months Ended September 30, 2020 2021 2020 2021 Controlling interest: Current taxes $ 4.4 $ 23.2 $ 25.0 $ 71.6 Intangible-related deferred taxes 27.0 12.0 (7.1) 51.9 Other deferred taxes 1.1 7.4 15.8 29.7 Total controlling interest 32.5 42.6 33.7 153.2 Non-controlling interests: Current taxes $ 3.1 $ 2.3 $ 7.4 $ 7.2 Deferred taxes 1.9 — 1.9 6.0 Total non-controlling interests 5.0 2.3 9.3 13.2 Income tax expense $ 37.5 $ 44.9 $ 43.0 $ 166.4 Income before income taxes (controlling interest) $ 103.8 $ 171.0 $ 120.0 $ 540.5 Effective tax rate (controlling interest) (1) 31.3 % 24.9 % 28.1 % 28.3 % ___________________________ (1) Taxes attributable to the controlling interest divided by income before income taxes (controlling interest). The Company’s effective tax rate (controlling interest) for the three months ended September 30, 2020 was higher than the marginal tax rate, primarily due to an $8.1 million deferred tax expense resulting from the revaluation of certain of the Company’s deferred tax liabilities due to an increase in the UK tax rate. The Company’s effective tax rate (controlling interest) for the nine months ended September 30, 2020 was higher than the marginal tax rate, primarily due to an $8.1 million deferred tax expense resulting from the revaluation of certain of the Company’s deferred tax liabilities due to an increase in the UK tax rate, as well as a $3.6 million tax expense related to share-

Earnings Per Share

Earnings Per Share	9 Months Ended
Earnings Per Share	Sep. 30, 2021
Earnings Per Share [Abstract]
Earnings Per Share	Earnings Per Share The calculation of Earnings per share (basic) is based on the weighted average number of shares of the Company’s common stock outstanding during the period. Earnings per share (diluted) is similar to Earnings per share (basic), but adjusts for the dilutive effect of the potential issuance of incremental shares of the Company’s common stock. The following is a reconciliation of the numerator and denominator used in the calculation of basic and diluted earnings per share available to common stockholders: For the Three Months Ended September 30, For the Nine Months Ended September 30, 2020 2021 2020 2021 Numerator Net income (controlling interest) $ 71.3 $ 128.4 $ 86.3 $ 387.3 Interest expense on junior convertible securities, net of taxes — 4.6 — 13.9 Net income (controlling interest), as adjusted $ 71.3 $ 133.0 $ 86.3 $ 401.2 Denominator Average shares outstanding (basic) 46.3 41.1 47.1 41.8 Effect of dilutive instruments: Stock options and restricted stock units 0.2 1.1 0.1 0.9 Junior convertible securities — 2.1 — 2.1 Average shares outstanding (diluted) 46.5 44.3 47.2 44.8 Average shares outstanding (diluted) in the table above excludes stock options and restricted stock units that have not met certain performance conditions and items that have an anti-dilutive effect on Earnings per share (diluted). The following is a summary of items excluded from the denominator in the table above: For the Three Months Ended September 30, For the Nine Months Ended September 30, 2020 2021 2020 2021 Stock options and restricted stock units 2.9 0.1 3.1 0.2 Junior convertible securities 2.2 — 2.2 — The Company may settle portions of its Affiliate equity purchases in shares of its common stock. Because it is the Company’s intention to settle these potential purchases in cash, the calculation of Average shares outstanding (diluted) excludes any potential dilutive effect from possible share settlements of Affiliate equity purchases. For the three and nine months ended September 30, 2021, under its authorized share repurchase programs, the Company repurchased 0.6 million and 2.8 million shares of its common stock, respectively, at an average price per share of $161.02 and $141.58, respectively.

Comprehensive Income

Comprehensive Income	9 Months Ended
Comprehensive Income	Sep. 30, 2021
Other Comprehensive Income (Loss), Net of Tax [Abstract]
Comprehensive Income	Comprehensive IncomeThe following table presents the tax effects allocated to each component of Other comprehensive income (loss): For the Three Months Ended September 30, 2020 2021 Pre-Tax Tax Expense Net of Tax Pre-Tax Tax Expense Net of Tax Foreign currency translation gain (loss) $ 25.2 $ (0.5) $ 24.7 $ (19.0) $ (0.7) $ (19.7) Change in net realized and unrealized gain (loss) on derivative financial instruments 0.2 — 0.2 (1.9) 0.0 (1.9) Other comprehensive income (loss) $ 25.4 $ (0.5) $ 24.9 $ (20.9) $ (0.7) $ (21.6) For the Nine Months Ended September 30, 2020 2021 Pre-Tax Tax (Expense) Benefit Net of Tax Pre-Tax Tax Expense Net of Tax Foreign currency translation gain (loss) $ (39.7) $ (11.7) $ (51.4) $ 18.6 $ (6.9) $ 11.7 Change in net realized and unrealized gain (loss) on derivative financial instruments (2.6) 0.5 (2.1) (0.9) (0.1) (1.0) Other comprehensive income (loss) $ (42.3) $ (11.2) $ (53.5) $ 17.7 $ (7.0) $ 10.7 The components of accumulated other comprehensive loss, net of taxes, were as follows: Foreign Realized and Total Balance, as of December 31, 2020 $ (161.9) $ (0.3) $ (162.2) Other comprehensive income before reclassifications 11.7 0.4 12.1 Amounts reclassified — (1.4) (1.4) Net other comprehensive income (loss) 11.7 (1.0) 10.7 Balance, as of September 30, 2021 $ (150.2) $ (1.3) $ (151.5)

Accounting Standards and Poli_2

Accounting Standards and Policies (Policies)	9 Months Ended
Accounting Standards and Policies (Policies)	Sep. 30, 2021
Accounting Policies [Abstract]
Basis of Presentation	The Consolidated Financial Statements of Affiliated Managers Group, Inc. (the “Company”) have been prepared in accordance with accounting principles generally accepted in the U.S. (“GAAP”) for interim financial information and with the instructions to Form 10-Q and Rule 10-01 of Regulation S-X. Accordingly, they do not include all of the information and footnotes required by GAAP for full year financial statements. In the opinion of management, all normal and recurring adjustments considered necessary for a fair statement of the Company’s interim financial position and results of operations have been included and all intercompany balances and transactions have been eliminated. Certain reclassifications have been made to the prior period’s financial statements to conform to the current period’s presentation. Operating results for interim periods are not necessarily indicative of the results that may be expected for any other period or for the full year. The Company’s Annual Report on Form 10-K for the fiscal year ended December 31, 2020 includes additional information about its operations, financial position, and accounting policies, and should be read in conjunction with this Quarterly Report on Form 10-Q.All amounts in these notes, except per share data in the text and tables herein, are stated in millions unless otherwise indicated
Use of Estimates	The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts and disclosures in the financial statements. Actual results could differ from those estimates.
Recently Adopted Accounting Standards and Recent Accounting Developments	Recently Adopted Accounting Standards Effective January 1, 2021, the Company adopted Accounting Standard Update (“ASU”) 2019-12, Simplifying the Accounting for Income Taxes. The adoption of this standard did not have a significant impact on the Company’s Consolidated Financial Statements. Recent Accounting Developments
Investments in Affiliates and Affiliate Sponsored Investments Products	Investments in Affiliates and Affiliate Sponsored Investment Products In evaluating whether an investment must be consolidated, the Company evaluates the risk, rewards, and significant terms of each of its Affiliates and other investments to determine if an investment is considered a voting rights entity (“VRE”) or a variable interest entity (“VIE”). An entity is a VRE when the total equity investment at risk is sufficient to enable the entity to finance its activities independently, and when the equity holders have the obligation to absorb losses, the right to receive residual returns, and the right to direct the activities of the entity that most significantly impact its economic performance. An entity is a VIE when it lacks one or more of the characteristics of a VRE, which, for the Company, are Affiliate investments structured as partnerships (or similar entities) where the Company is a limited partner and lacks substantive kick-out or substantive participation rights over the general partner. Assessing whether an entity is a VRE or VIE involves judgment. Upon the occurrence of certain events, management reviews and reconsiders its previous conclusion regarding the status of an entity as a VRE or a VIE. The Company consolidates VREs when it has control over significant operating, financial, and investing decisions of the entity. When the Company lacks such control, but is deemed to have significant influence, the Company accounts for the VRE under the equity method. Other investments with readily determinable fair values in which the Company does not have rights to exercise significant influence are recorded at fair value on the Consolidated Balance Sheets, with changes in fair value included in Investment and other income. The Company consolidates VIEs when it is the primary beneficiary of the entity, which is defined as having the power to direct the activities that most significantly impact the VIE’s economic performance and the obligation to absorb losses of, or the right to receive benefits from, the entity that could potentially be significant to the VIE. Substantially all of the Company’s consolidated Affiliates considered VIEs are controlled because the Company holds a majority of the voting interests or it is the managing member or general partner. Furthermore, an Affiliate’s assets can be used for purposes other than the settlement of the respective Affiliate’s obligations. The Company applies the equity method of accounting to VIEs where the Company is not the primary beneficiary, but has the ability to exercise significant influence over operating and financial matters of the VIE. Investments in Affiliates Substantially all of the Company’s Affiliates are considered VIEs and are either consolidated or accounted for under the equity method. A limited number of the Company’s Affiliates are considered VREs and most of these are accounted for under the equity method. When an Affiliate is consolidated, the portion of the earnings attributable to Affiliate management’s equity ownership is included in Net income (non-controlling interests) in the Consolidated Statements of Income. Undistributed earnings attributable to Affiliate managements’ equity ownership, along with their share of any tangible or intangible net assets, are presented within Non-controlling interests on the Consolidated Balance Sheets. Affiliate equity interests where the holder has certain rights to demand settlement are presented, at their current redemption values, as Redeemable non-controlling interests on the Consolidated Balance Sheets. The Company periodically issues, sells, and purchases the equity of its consolidated Affiliates. Because these transactions take place between entities that are under common control, any gains or losses attributable to these transactions are required to be included in Additional paid-in capital in the Consolidated Balance Sheets, net of any related income tax effects in the period the transaction occurs. When an Affiliate is accounted for under the equity method, the Company’s share of an Affiliate’s earnings or losses, net of amortization and impairments, is included in Equity method income (loss) (net) in the Consolidated Statements of Income and the carrying value of the Affiliate is reported in Equity method investments in Affiliates (net) in the Consolidated Balance Sheets. Deferred taxes recorded on intangible assets upon acquisition of an Affiliate accounted for under the equity method are presented on a gross basis within Equity method investments in Affiliates (net) and Deferred income tax liability (net) in the Consolidated Balance Sheets. The Company’s share of income taxes incurred directly by Affiliates accounted for under the equity method is recorded in Income tax expense in the Consolidated Statements of Income. The Company periodically performs assessments to determine if the fair value of an investment may have declined below its related carrying value for its Affiliates accounted for under the equity method for a period that the Company considers to be other-than-temporary. Where the Company believes that such declines may have occurred, the Company determines the amount of impairment using valuation methods, such as discounted cash flow analyses. Impairments are recorded as an expense in Equity method income (loss) (net) to reduce the carrying value of the Affiliate to its fair value. Affiliate Sponsored Investment Products The Company’s Affiliates sponsor various investment products where the Affiliate also acts as the investment adviser. These investment products are typically owned primarily by third-party investors; however, certain products are funded with general partner and seed capital investments from the Company and its Affiliates. Third-party investors in Affiliate sponsored investment products are generally entitled to substantially all of the economics of these products, except for the asset- and performance-based fees earned by the Company’s Affiliates or any gains or losses attributable to the Company’s or its Affiliates’ investments in these products. As a result, the Company generally does not consolidate these products unless the Company’s or its consolidated Affiliate’s interest in the product is considered substantial. When the Company’s or its consolidated Affiliates’ interests are considered substantial and the products are consolidated, the

Investments in Marketable Sec_2

Investments in Marketable Securities (Tables)	9 Months Ended
Investments in Marketable Securities (Tables)	Sep. 30, 2021
Marketable Securities [Abstract]
Schedule of Investments in Marketable Securities	The following table summarizes the cost, gross unrealized gains, gross unrealized losses, and fair value of Investments in marketable securities: December 31, September 30, Cost $ 69.4 $ 68.5 Unrealized gains 5.5 8.2 Unrealized losses (0.0 ) (0.9) Fair value $ 74.9 $ 75.8

Other Investments (Tables)

Other Investments (Tables)	9 Months Ended
Other Investments (Tables)	Sep. 30, 2021
Investments, All Other Investments [Abstract]
Schedule of Other Investments and Unfunded Commitments	The following table summarizes the fair value of these investments and any related unfunded commitments: December 31, 2020 September 30, 2021 Category of Investment Fair Value Unfunded Fair Value Unfunded Private equity funds (1) $ 235.4 $ 122.2 $ 307.0 $ 114.1 Investments in other strategies (2) 8.0 — 16.6 — Total (3) $ 243.4 $ 122.2 $ 323.6 $ 114.1 ___________________________ (1) The Company accounts for the majority of its interests in private equity funds under the equity method of accounting and uses NAV as a practical expedient, one quarter in arrears (adjusted for current period calls and distributions), to determine the fair value. These funds primarily invest in a broad range of third-party funds and direct investments. Distributions will be received as the underlying assets are liquidated over the life of the funds, which is generally up to 15 years. (2) These are multi-disciplinary funds that invest across various asset classes and strategies, including equity, credit, and real estate. Investments are generally redeemable on a daily, monthly, or quarterly basis. (3) Fair value attributable to the controlling interest was $164.4 million and $217.7 million as of December 31, 2020 and September 30, 2021, respectively.
Schedule of Investments without Readily Determinable Fair Value	Investments Without Readily Determinable Fair Values The following table summarizes the cost, cumulative upward adjustments, and carrying amount of investments without readily determinable fair values: December 31, September 30, Cost $ 8.5 $ 8.5 Cumulative upward adjustments 5.3 25.0 Carrying amount $ 13.8 $ 33.5

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	9 Months Ended
Fair Value Measurements (Tables)	Sep. 30, 2021
Fair Value Disclosures [Abstract]
Schedule of Fair Value of Assets and Liabilities Measured on a Recurring Basis	The following tables summarize the Company’s financial assets and liabilities that are measured at fair value on a recurring basis: Fair Value Measurements December 31, Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Financial Assets Investments in marketable securities $ 74.9 $ 25.7 $ 49.2 $ — Derivative financial instruments (1) 3.5 — 3.5 — Financial Liabilities (2) Affiliate equity purchase obligations $ 22.0 $ — $ — $ 22.0 Derivative financial instruments 4.2 — 4.2 — Fair Value Measurements September 30, Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Financial Assets Investments in marketable securities $ 75.8 $ 61.1 $ 14.7 $ — Derivative financial instruments (1) 1.0 — 1.0 — Financial Liabilities (2) Affiliate equity purchase obligations $ 47.7 $ — $ — $ 47.7 Derivative financial instruments 2.5 — 2.5 — __________________________ (1) Amounts are presented within Other assets on the Consolidated Balance Sheets. (2) Amounts are presented within Other liabilities on the Consolidated Balance Sheets.
Schedule of Changes in Level 3 Assets and Liabilities for Affiliate equity repurchase obligation	The following table presents the changes in level 3 liabilities for Affiliate equity purchase obligations: For the Three Months Ended September 30, For the Nine Months Ended September 30, 2020 2021 2020 2021 Balance, beginning of period $ 73.3 $ 47.9 $ 19.8 $ 22.0 Net realized and unrealized (gains) losses (1) (0.2) — (4.1) 2.2 Purchases and issuances (2) 85.8 3.3 292.8 86.3 Settlements and reductions (89.0) (3.5) (238.6) (62.8) Balance, end of period $ 69.9 $ 47.7 $ 69.9 $ 47.7 Net change in unrealized (gains) losses relating to instruments still held at the reporting date $ — $ — $ — $ — ___________________________ (1) Accretion expense for these arrangements and obligations is recorded in Interest expense in the Consolidated Statements of Income. (2) Includes transfers from Redeemable non-controlling interests.
Schedule of Quantitative Information used in Valuing Level 3 Liabilities	The following table presents certain quantitative information about the significant unobservable inputs used in valuing the Company’s level 3 fair value measurements: Quantitative Information About Level 3 Fair Value Measurements December 31, 2020 September 30, 2021 Valuation Unobservable Fair Value Range Weighted Average (1) Fair Value Range Weighted Average (1) Affiliate equity purchase obligations Discounted cash flow Growth rates (2) $ 22.0 (5)% - 8% 3 % $ 47.7 1% - 8% 5 % Discount rates 14% - 16% 15 % 15% - 17% 15 % ___________________________ (1) Calculated by comparing the relative fair value of an obligation to its respective total.
Schedule of Other Financial Assets and Liabilities Not Carried at Fair Value	The following table summarizes the Company’s other financial liabilities not carried at fair value: December 31, 2020 September 30, 2021 Carrying Value Fair Value Carrying Value Fair Value Fair Value Hierarchy Senior notes $ 1,097.3 $ 1,206.6 $ 1,097.8 $ 1,180.7 Level 2 Junior subordinated notes 565.7 623.1 765.8 804.3 Level 2 Junior convertible securities 318.4 427.6 301.4 457.7 Level 2

Investments in Affiliates and_2

Investments in Affiliates and Affiliate Sponsored Investment Products (Tables)	9 Months Ended
	Sep. 30, 2021
Variable Interest Entities
Schedule of Unconsolidated Assets and Liabilities of Equity Method Investments and Company's Risk of Loss	The unconsolidated assets, net of liabilities and non-controlling interests of Affiliates accounted for under the equity method considered VIEs, and the Company’s carrying value and maximum exposure to loss, were as follows: December 31, 2020 September 30, 2021 Unconsolidated Carrying Value and Unconsolidated Carrying Value and Affiliates accounted for under the equity method $ 1,384.2 $ 1,962.1 $ 1,194.6 $ 1,976.7 December 31, 2020 September 30, 2021 Unconsolidated Carrying Value and Unconsolidated Carrying Value and Affiliate sponsored investment products $ 2,378.2 $ 0.9 $ 3,155.9 $ 13.6

Debt (Tables)

Debt (Tables)	9 Months Ended
Debt (Tables)	Sep. 30, 2021
Debt Disclosure [Abstract]
Schedule of Debt	The following table summarizes the Company’s Debt: December 31, September 30, Senior bank debt $ 349.8 $ 349.8 Senior notes 1,091.9 1,093.1 Junior subordinated notes 556.4 751.4 Junior convertible securities 314.0 297.5 Debt $ 2,312.1 $ 2,491.8
Schedule of Principal Terms of Senior and Junior Subordinated Notes	The principal terms of the senior notes outstanding as of September 30, 2021 were as follows: 2024 2025 2030 Issue date February 2014 February 2015 June 2020 Maturity date February 2024 August 2025 June 2030 Par value (in millions) $ 400.0 $ 350.0 $ 350.0 Stated coupon 4.25 % 3.50 % 3.30 % Coupon frequency Semi-annually Semi-annually Semi-annually Potential call date Any time Any time Any time Call price As defined As defined As defined The principal terms of the junior subordinated notes outstanding as of September 30, 2021 were as follows: 2059 2060 2061 Issue date March 2019 September 2020 July 2021 Maturity date March 2059 September 2060 September 2061 Par value (in millions) $ 300.0 $ 275.0 $ 200.0 Stated coupon 5.875 % 4.75 % 4.20 % Coupon frequency Quarterly Quarterly Quarterly Potential call date March 2024 September 2025 September 2026 Call price As defined As defined As defined Listing NYSE NYSE NYSE

Derivative Financial Instrume_2

Derivative Financial Instruments (Tables)	9 Months Ended
Derivative Financial Instruments (Tables)	Sep. 30, 2021
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Schedule of Company's Derivative Assets and Liabilities Measured at Fair Value on Recurring Basis	The following table summarizes the Company’s and its Affiliates’ derivative financial instruments measured at fair value on a recurring basis: December 31, 2020 September 30, 2021 Assets Liabilities Assets Liabilities Forward foreign currency contracts $ 3.5 $ (2.3) $ 1.0 $ (1.4) Interest rate swap — (1.9) — (1.1) Total $ 3.5 $ (4.2) $ 1.0 $ (2.5)
Schedule of Effect of Derivative Financial Instruments on the Consolidated Statements of Comprehensive Income and Statements of Income	The following table summarizes the effects of derivative financial instruments on the Consolidated Statements of Comprehensive Income and the Consolidated Statements of Income: For the Three Months Ended September 30, 2020 2021 Gain (Loss) Recognized in Other Comprehensive Income Gain Reclassified from Accumulated Other Comprehensive Loss into Earnings Gain (Loss) Recognized in Earnings from Excluded Components (1) Gain (Loss) Recognized in Other Comprehensive Income Gain Reclassified from Accumulated Other Comprehensive Loss into Earnings Gain (Loss) Recognized in Earnings from Excluded Components (1) Forward foreign currency contracts $ 0.4 $ 0.1 $ — $ (2.0) $ 0.4 $ — Interest rate swap (0.1) — — 0.1 — — Total $ 0.3 $ 0.1 $ — $ (1.9) $ 0.4 $ — For the Nine Months Ended September 30, 2020 2021 Gain (Loss) Recognized in Other Comprehensive Loss Gain Reclassified from Accumulated Other Comprehensive Loss into Earnings Gain Recognized in Earnings from Excluded Components (1) Gain (Loss) Recognized in Other Comprehensive Income Gain Reclassified from Accumulated Other Comprehensive Loss into Earnings Gain (Loss) Recognized in Earnings from Excluded Components (1) Forward foreign currency contracts $ 64.9 $ 0.4 $ 2.8 $ (1.6) $ 1.4 $ — Put options (47.7) — — — — — Call options (1.3) — — — — — Interest rate swap (2.1) — — 0.7 — — Total $ 13.8 $ 0.4 $ 2.8 $ (0.9) $ 1.4 $ — ___________________________ (1) The excluded components of the forward foreign currency contracts were recognized in earnings on a straight-line basis over the respective period of the contracts as a reduction to Interest expense.

Goodwill and Acquired Client _2

Goodwill and Acquired Client Relationships (Tables)	9 Months Ended
Goodwill and Acquired Client Relationships (Tables)	Sep. 30, 2021
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of Changes in Goodwill	The following tables present the changes in the Company’s consolidated Affiliates’ Goodwill and components of Acquired client relationships (net): Goodwill Balance, as of December 31, 2020 $ 2,661.4 Foreign currency translation (2.9) Balance, as of September 30, 2021 $ 2,658.5 As of September 30, 2021, the Company completed its annual impairment assessment on goodwill and no impairment was indicated.
Schedule of Changes in the Components of Acquired Client Relationships	Acquired Client Relationships (Net) Definite-lived Indefinite-lived Total Gross Book Accumulated Net Book Net Book Net Book Balance, as of December 31, 2020 $ 1,166.6 $ (1,026.8) $ 139.8 $ 909.0 $ 1,048.8 Intangible amortization and impairments — (25.3) (25.3) — (25.3) Foreign currency translation (0.2) 0.1 (0.1) (5.2) (5.3) Balance, as of September 30, 2021 $ 1,166.4 $ (1,052.0) $ 114.4 $ 903.8 $ 1,018.2

Equity Method Investments in _2

Equity Method Investments in Affiliates (Tables)	9 Months Ended
Equity Method Investments in Affiliates (Tables)	Sep. 30, 2021
Equity Method Investments and Joint Ventures [Abstract]
Schedule of Changes in Equity Method Investments in Affiliates	The following table presents the change in Equity method investments in Affiliates (net): Equity Method Investments in Affiliates (Net) Balance, as of December 31, 2020 $ 2,074.8 Investments in Affiliates 144.3 Earnings 218.9 Intangible amortization and impairments (93.8) Distributions of earnings (288.1) Return of capital (3.4) Foreign currency translation 25.8 Other 6.7 Balance, as of September 30, 2021 $ 2,085.2

Share-Based Compensation (Table

Share-Based Compensation (Tables)	9 Months Ended
Share-Based Compensation (Tables)	Sep. 30, 2021
Share-based Payment Arrangement [Abstract]
Schedule of Share-Based Compensation	The following table presents share-based compensation expense: For the Three Months Ended September 30, For the Nine Months Ended September 30, 2020 2021 2020 2021 Share-based compensation $ 15.7 $ 21.2 $ 46.4 $ 44.5 Tax benefit 2.9 3.5 8.4 7.8
Schedule of Company Restricted Stock Units Transactions	The following table summarizes transactions in the Company’s restricted stock units: Restricted Stock Units Weighted Average Grant Date Value Unvested units - December 31, 2020 1.2 $ 99.46 Units granted 0.2 139.71 Units vested (0.3) 130.58 Units forfeited (0.1) 105.45 Performance condition changes 0.1 80.19 Unvested units - September 30, 2021 1.1 94.22
Schedule of Company Stock Option Transactions	The following table summarizes transactions in the Company’s stock options: Stock Options Weighted Average Weighted Average Unexercised options outstanding - December 31, 2020 2.9 $ 82.14 Options granted 0.0 150.68 Options exercised (0.2) 120.12 Options forfeited (0.0 ) 154.44 Performance condition changes 0.6 74.42 Unexercised options outstanding - September 30, 2021 3.3 78.21 4.8 Exercisable at September 30, 2021 0.2 131.74 1.6
Schedule of Fair Value of Options Granted and Assumptions	The weighted average grant date assumptions used to estimate the fair value of stock options granted were as follows: For the Nine Months Ended September 30, 2020 2021 Dividend yield 1.6 % 0.0 % Expected volatility 30.4 % 37.1 % Risk-free interest rate 0.9 % 1.0 % Expected life of options (in years) 5.7 5.7 Forfeiture rate — % — %

Redeemable Non-Controlling In_2

Redeemable Non-Controlling Interests (Tables)	9 Months Ended
Redeemable Non-Controlling Interests (Tables)	Sep. 30, 2021
Noncontrolling Interest [Abstract]
Schedule of Changes in Redeemable Non-Controlling Interests	The following table presents the changes in Redeemable non-controlling interests: Redeemable Non-controlling Interests Balance, as of December 31, 2020 (1) $ 671.5 Decrease attributable to consolidated Affiliate sponsored investment products (17.1) Transfers to Other liabilities (86.3) Transfers from Non-controlling interests 3.9 Changes in redemption value 176.9 Balance, as of September 30, 2021 (1) $ 748.9 ___________________________ (1) As of December 31, 2020 and September 30, 2021, Redeemable non-controlling interests include consolidated Affiliate sponsored investment products primarily attributable to third-party investors of $35.4 million and $18.3 million, respectively.

Affiliate Equity (Tables)

Affiliate Equity (Tables)	9 Months Ended
Affiliate Equity (Tables)	Sep. 30, 2021
Affiliate Equity [Abstract]
Schedule of Affiliate Equity Compensation	The following table presents Affiliate equity compensation expense: For the Three Months Ended September 30, For the Nine Months Ended September 30, 2020 2021 2020 2021 Controlling interest $ 3.5 $ 2.8 $ 11.4 $ 9.9 Non-controlling interests 6.0 8.9 24.9 36.5 Total $ 9.5 $ 11.7 $ 36.3 $ 46.4
Schedule of Affiliate Equity Unrecognized Compensation Expense	The following table presents unrecognized Affiliate equity compensation expense: Controlling Interest Remaining Life Non-controlling Interests Remaining Life December 31, 2020 $ 35.9 4 years $ 109.7 5 years September 30, 2021 47.6 5 years 108.1 4 years
Schedule of Changes in the Company's Interest in its Affiliates on the Controlling Interest's Equity	While the Company presents the current redemption value of Affiliate equity within Redeemable non-controlling interests, with changes in the current redemption value increasing or decreasing the controlling interest’s equity over time, the following table presents the cumulative effect that ownership changes had on the controlling interest’s equity related only to Affiliate equity transactions that settled during the applicable periods: For the Three Months Ended September 30, For the Nine Months Ended September 30, 2020 2021 2020 2021 Net income (controlling interest) $ 71.3 $ 128.4 $ 86.3 $ 387.3 Increase (decrease) in controlling interest paid-in capital from Affiliate equity issuances 2.9 — 1.6 (17.5) Decrease in controlling interest paid-in capital from Affiliate equity purchases (65.4) (1.2) (226.0) (57.2) Net income (loss) (controlling interest) including the net impact of Affiliate equity transactions $ 8.8 $ 127.2 $ (138.1) $ 312.6

Income Taxes (Tables)

Income Taxes (Tables)	9 Months Ended
Income Taxes (Tables)	Sep. 30, 2021
Income Tax Disclosure [Abstract]
Schedule of Income Tax Provisions by Controlling and Noncontrolling Interests	The following table presents the consolidated provision for income taxes: For the Three Months Ended September 30, For the Nine Months Ended September 30, 2020 2021 2020 2021 Controlling interest: Current taxes $ 4.4 $ 23.2 $ 25.0 $ 71.6 Intangible-related deferred taxes 27.0 12.0 (7.1) 51.9 Other deferred taxes 1.1 7.4 15.8 29.7 Total controlling interest 32.5 42.6 33.7 153.2 Non-controlling interests: Current taxes $ 3.1 $ 2.3 $ 7.4 $ 7.2 Deferred taxes 1.9 — 1.9 6.0 Total non-controlling interests 5.0 2.3 9.3 13.2 Income tax expense $ 37.5 $ 44.9 $ 43.0 $ 166.4 Income before income taxes (controlling interest) $ 103.8 $ 171.0 $ 120.0 $ 540.5 Effective tax rate (controlling interest) (1) 31.3 % 24.9 % 28.1 % 28.3 % ___________________________ (1) Taxes attributable to the controlling interest divided by income before income taxes (controlling interest).

Earnings Per Share (Tables)

Earnings Per Share (Tables)	9 Months Ended
Earnings Per Share (Tables)	Sep. 30, 2021
Earnings Per Share [Abstract]
Schedule of Basic and Diluted Earnings (Loss) Per Share	The following is a reconciliation of the numerator and denominator used in the calculation of basic and diluted earnings per share available to common stockholders: For the Three Months Ended September 30, For the Nine Months Ended September 30, 2020 2021 2020 2021 Numerator Net income (controlling interest) $ 71.3 $ 128.4 $ 86.3 $ 387.3 Interest expense on junior convertible securities, net of taxes — 4.6 — 13.9 Net income (controlling interest), as adjusted $ 71.3 $ 133.0 $ 86.3 $ 401.2 Denominator Average shares outstanding (basic) 46.3 41.1 47.1 41.8 Effect of dilutive instruments: Stock options and restricted stock units 0.2 1.1 0.1 0.9 Junior convertible securities — 2.1 — 2.1 Average shares outstanding (diluted) 46.5 44.3 47.2 44.8
Schedule of Shares Excluded from Calculation of Basic and Diluted Earnings (Loss) Per Share	The following is a summary of items excluded from the denominator in the table above: For the Three Months Ended September 30, For the Nine Months Ended September 30, 2020 2021 2020 2021 Stock options and restricted stock units 2.9 0.1 3.1 0.2 Junior convertible securities 2.2 — 2.2 —

Comprehensive Income (Tables)

Comprehensive Income (Tables)	9 Months Ended
Comprehensive Income (Tables)	Sep. 30, 2021
Other Comprehensive Income (Loss), Net of Tax [Abstract]
Schedule of Tax Effects Allocated to Each Component of Other Comprehensive Income (Loss)	The following table presents the tax effects allocated to each component of Other comprehensive income (loss): For the Three Months Ended September 30, 2020 2021 Pre-Tax Tax Expense Net of Tax Pre-Tax Tax Expense Net of Tax Foreign currency translation gain (loss) $ 25.2 $ (0.5) $ 24.7 $ (19.0) $ (0.7) $ (19.7) Change in net realized and unrealized gain (loss) on derivative financial instruments 0.2 — 0.2 (1.9) 0.0 (1.9) Other comprehensive income (loss) $ 25.4 $ (0.5) $ 24.9 $ (20.9) $ (0.7) $ (21.6) For the Nine Months Ended September 30, 2020 2021 Pre-Tax Tax (Expense) Benefit Net of Tax Pre-Tax Tax Expense Net of Tax Foreign currency translation gain (loss) $ (39.7) $ (11.7) $ (51.4) $ 18.6 $ (6.9) $ 11.7 Change in net realized and unrealized gain (loss) on derivative financial instruments (2.6) 0.5 (2.1) (0.9) (0.1) (1.0) Other comprehensive income (loss) $ (42.3) $ (11.2) $ (53.5) $ 17.7 $ (7.0) $ 10.7
Schedule of Components of Accumulated Other Comprehensive Loss	The components of accumulated other comprehensive loss, net of taxes, were as follows: Foreign Realized and Total Balance, as of December 31, 2020 $ (161.9) $ (0.3) $ (162.2) Other comprehensive income before reclassifications 11.7 0.4 12.1 Amounts reclassified — (1.4) (1.4) Net other comprehensive income (loss) 11.7 (1.0) 10.7 Balance, as of September 30, 2021 $ (150.2) $ (1.3) $ (151.5)

Accounting Standards and Poli_3

Accounting Standards and Policies (Details) - USD ($) $ in Millions	Dec. 31, 2021	Sep. 30, 2021	Dec. 31, 2020
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Increase in debt		$ 2,491.8	$ 2,312.1
Increase in retained earnings		4,391.5	4,005.5
Decrease in additional paid-in-capital		(556)	(728.9)
Decrease in deferred income tax liability (net)		$ (513.9)	$ (423.4)
Accounting Standards Update 2020-06 \| Forecast
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Increase in debt	$ 102.4
Increase in retained earnings	4.6
Decrease in additional paid-in-capital	81.4
Decrease in deferred income tax liability (net)	$ 25.6

Investments in Marketable Sec_3

Investments in Marketable Securities - Cost, Gross Unrealized Gains and Losses and Fair Value (Details) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Marketable Securities [Abstract]
Cost	$ 68.5	$ 69.4
Unrealized gains	8.2	5.5
Unrealized losses	(0.9)	0
Fair value	$ 75.8	$ 74.9

Investments in Marketable Sec_4

Investments in Marketable Securities - Additional Information (Details) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Variable Interest Entity, Primary Beneficiary
Investments in and Advances to Affiliates [Line Items]
Fair value of deconsolidated investment in affiliate	$ 19	$ 52.3

Other Investments - Investments

Other Investments - Investments Measured at NAV as a Practical Expedient (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2021	Dec. 31, 2020
NAV of investments at fair value
Unfunded Commitments	$ 114.1	$ 122.2
Life of funds (generally up to)	15 years
Private equity funds
NAV of investments at fair value
Unfunded Commitments	$ 114.1	122.2
Investments in other strategies
NAV of investments at fair value
Unfunded Commitments	0	0
Fair Value Measured at NAV
NAV of investments at fair value
Fair Value	323.6	243.4
Fair Value Measured at NAV \| Controlling Interest
NAV of investments at fair value
Fair Value	217.7	164.4
Fair Value Measured at NAV \| Private equity funds
NAV of investments at fair value
Fair Value	307	235.4
Fair Value Measured at NAV \| Investments in other strategies
NAV of investments at fair value
Fair Value	$ 16.6	$ 8

Other Investments - Investmen_2

Other Investments - Investments without Readily Determinable Fair Value (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2021	Dec. 31, 2020
Investments, All Other Investments [Abstract]
Cost	$ 8.5	$ 8.5	$ 8.5
Cumulative upward adjustments	25	25	5.3
Carrying amount	33.5	33.5	$ 13.8
Upward adjustments	$ 19.7	$ 19.7

Fair Value Measurements - Asset

Fair Value Measurements - Assets and Liabilities Measured on a Recurring Basis (Details) - Fair Value Measured on a Recurring Basis - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Financial Assets
Investments in marketable securities	$ 75.8	$ 74.9
Derivative financial instruments	1	3.5
Financial Liabilities
Affiliate equity purchase obligations	47.7	22
Derivative financial instruments	2.5	4.2
Quoted Prices in Active Markets for Identical Assets (Level 1)
Financial Assets
Investments in marketable securities	61.1	25.7
Derivative financial instruments	0	0
Financial Liabilities
Affiliate equity purchase obligations	0	0
Derivative financial instruments	0	0
Significant Other Observable Inputs (Level 2)
Financial Assets
Investments in marketable securities	14.7	49.2
Derivative financial instruments	1	3.5
Financial Liabilities
Affiliate equity purchase obligations	0	0
Derivative financial instruments	2.5	4.2
Significant Unobservable Inputs (Level 3)
Financial Assets
Investments in marketable securities	0	0
Derivative financial instruments	0	0
Financial Liabilities
Affiliate equity purchase obligations	47.7	22
Derivative financial instruments	$ 0	$ 0

Fair Value Measurements - Chang

Fair Value Measurements - Changes in Level 3 Liabilities (Details) - Significant Unobservable Inputs (Level 3) - Affiliate equity purchase obligations - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, beginning of period	$ 47.9	$ 73.3	$ 22	$ 19.8
Net realized and unrealized (gains) losses	0	(0.2)	2.2	(4.1)
Purchases and issuances	3.3	85.8	86.3	292.8
Settlements and reductions	(3.5)	(89)	(62.8)	(238.6)
Balance, end of period	47.7	69.9	47.7	69.9
Net change in unrealized (gains) losses relating to instruments still held at the reporting date	$ 0	$ 0	$ 0	$ 0

Fair Value Measurements - Quant

Fair Value Measurements - Quantitative Information used in Valuing Level 3 Liabilities (Details) - Significant Unobservable Inputs (Level 3) - Affiliate equity purchase obligations - Discounted cash flow $ in Millions	Sep. 30, 2021USD ($)	Dec. 31, 2020USD ($)
Quantitative information for Level 3 Fair Value Measurements Liabilities
Fair Value	$ 47.7	$ 22
Growth rates \| Minimum
Quantitative information for Level 3 Fair Value Measurements Liabilities
Affiliate equity purchase obligations, measurement input	0.01	(0.05)
Growth rates \| Maximum
Quantitative information for Level 3 Fair Value Measurements Liabilities
Affiliate equity purchase obligations, measurement input	0.08	0.08
Growth rates \| Weighted Average
Quantitative information for Level 3 Fair Value Measurements Liabilities
Affiliate equity purchase obligations, measurement input	0.05	0.03
Discount rates \| Minimum
Quantitative information for Level 3 Fair Value Measurements Liabilities
Affiliate equity purchase obligations, measurement input	0.15	0.14
Discount rates \| Maximum
Quantitative information for Level 3 Fair Value Measurements Liabilities
Affiliate equity purchase obligations, measurement input	0.17	0.16
Discount rates \| Weighted Average
Quantitative information for Level 3 Fair Value Measurements Liabilities
Affiliate equity purchase obligations, measurement input	0.15	0.15

Fair Value Measurements - Other

Fair Value Measurements - Other Financial Assets and Liabilities Not Carried at Fair Value (Details) - Level 2 - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Carrying Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Senior notes	$ 1,097.8	$ 1,097.3
Junior subordinated notes	765.8	565.7
Junior convertible securities	301.4	318.4
Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Senior notes	1,180.7	1,206.6
Junior subordinated notes	804.3	623.1
Junior convertible securities	$ 457.7	$ 427.6

Investments in Affiliates and_3

Investments in Affiliates and Affiliate Sponsored Investment Products - Affiliated Accounted For Under Equity Method (Details) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Variable Interest Entities
Carrying value of equity method investment in affiliate	$ 2,085.2	$ 2,074.8
Carrying amount and maximum exposure to loss equity method investments considered VREs	108.5	112.7
Variable Interest Entity, Not Primary Beneficiary
Variable Interest Entities
Unconsolidated VIE Net Assets	1,194.6	1,384.2
Carrying Value and Maximum Exposure to Loss	$ 1,976.7	$ 1,962.1

Investments in Affiliates and_4

Investments in Affiliates and Affiliate Sponsored Investment Products - Affiliated Sponsored Investment Products (Details) - Variable Interest Entity, Primary Beneficiary - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Variable Interest Entities
Unconsolidated VIE Net Assets	$ 3,155.9	$ 2,378.2
Carrying Value and Maximum Exposure to Loss	$ 13.6	$ 0.9

Debt - Schedule of Debt (Detail

Debt - Schedule of Debt (Details) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Debt	$ 2,491.8	$ 2,312.1
Senior bank debt
Debt Instrument [Line Items]
Debt	349.8	349.8
Senior notes
Debt Instrument [Line Items]
Debt	1,093.1	1,091.9
Junior subordinated notes
Debt Instrument [Line Items]
Debt	751.4	556.4
Junior convertible securities
Debt Instrument [Line Items]
Debt	$ 297.5	$ 314

Debt - Senior Bank Debt (Detail

Debt - Senior Bank Debt (Details) - Senior bank debt - USD ($)	9 Months Ended
	Sep. 30, 2021	Dec. 31, 2020
Revolver
Debt Instrument [Line Items]
Available borrowing	$ 1,250,000,000
Additional borrowing amount	500,000,000
Borrowings outstanding	0	$ 0
Term Loan
Debt Instrument [Line Items]
Available borrowing	350,000,000
Additional borrowing amount	$ 75,000,000
Term Loan \| LIBOR
Debt Instrument [Line Items]
Basis spread on debt variable rate	0.85%

Debt - Schedule of Principal Te

Debt - Schedule of Principal Terms of Senior and Junior Subordinated Notes (Details)	Sep. 30, 2021USD ($)
Senior notes \| 2024 Senior Notes
Debt Instrument [Line Items]
Par value	$ 400,000,000
Stated coupon	4.25%
Senior notes \| 2025 Senior Notes
Debt Instrument [Line Items]
Par value	$ 350,000,000
Stated coupon	3.50%
Senior notes \| 2030 Senior Notes
Debt Instrument [Line Items]
Par value	$ 350,000,000
Stated coupon	3.30%
Junior subordinated notes \| 2059 Junior Subordinated Notes
Debt Instrument [Line Items]
Par value	$ 300,000,000
Stated coupon	5.875%
Junior subordinated notes \| 2060 Junior Subordinated Notes
Debt Instrument [Line Items]
Par value	$ 275,000,000
Stated coupon	4.75%
Junior subordinated notes \| 2061 Junior Subordinated Notes
Debt Instrument [Line Items]
Par value	$ 200,000,000
Stated coupon	4.20%

Debt - Senior Notes and Junior

Debt - Senior Notes and Junior Subordinated Notes (Details)	9 Months Ended
Debt - Senior Notes and Junior Subordinated Notes (Details)	Sep. 30, 2021
2024 Senior Notes \| Senior notes
Debt Instrument [Line Items]
Redemption price percentage	100.00%
2024 Senior Notes \| Senior notes \| Treasury Rate
Debt Instrument [Line Items]
Applicable basis spread over redemption price percentage	0.25%
2025 Senior Notes \| Senior notes
Debt Instrument [Line Items]
Redemption price percentage	100.00%
2025 Senior Notes \| Senior notes \| Treasury Rate
Debt Instrument [Line Items]
Applicable basis spread over redemption price percentage	0.25%
2030 Senior Notes \| Senior notes
Debt Instrument [Line Items]
Redemption price percentage	100.00%
2030 Senior Notes \| Senior notes \| Treasury Rate
Debt Instrument [Line Items]
Applicable basis spread over redemption price percentage	0.40%
5.875% Junior Subordinated Notes due 2059 \| Junior subordinated notes \| On or after September 30, 2026
Debt Instrument [Line Items]
Redemption price percentage	100.00%
5.875% Junior Subordinated Notes due 2059 \| Junior subordinated notes \| If changes in tax laws and interpretations occur
Debt Instrument [Line Items]
Redemption price percentage	100.00%
5.875% Junior Subordinated Notes due 2059 \| Junior subordinated notes \| If a rating agency makes certain changes relating to the equity credit criteria for securities
Debt Instrument [Line Items]
Redemption price percentage	102.00%
4.750% Junior Subordinated Notes due 2060 \| Junior subordinated notes \| On or after September 30, 2026
Debt Instrument [Line Items]
Redemption price percentage	100.00%
4.750% Junior Subordinated Notes due 2060 \| Junior subordinated notes \| If changes in tax laws and interpretations occur
Debt Instrument [Line Items]
Redemption price percentage	100.00%
4.750% Junior Subordinated Notes due 2060 \| Junior subordinated notes \| If a rating agency makes certain changes relating to the equity credit criteria for securities
Debt Instrument [Line Items]
Redemption price percentage	102.00%
4.200% Junior Subordinated Notes due 2061 \| Junior subordinated notes \| On or after September 30, 2026
Debt Instrument [Line Items]
Redemption price percentage	100.00%
4.200% Junior Subordinated Notes due 2061 \| Junior subordinated notes \| If changes in tax laws and interpretations occur
Debt Instrument [Line Items]
Redemption price percentage	100.00%
4.200% Junior Subordinated Notes due 2061 \| Junior subordinated notes \| If a rating agency makes certain changes relating to the equity credit criteria for securities
Debt Instrument [Line Items]
Redemption price percentage	102.00%

Debt - Junior Convertible Secur

Debt - Junior Convertible Securities (Details) - USD ($)	3 Months Ended	9 Months Ended
Debt - Junior Convertible Securities (Details) - USD ($)	Sep. 30, 2021	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Debt Instrument [Line Items]
Debt	$ 2,491,800,000	$ 2,491,800,000		$ 2,312,100,000
Repayments of long-term debt		26,100,000	$ 350,000,000
Repurchase of junior convertible securities, equity impact	1,300,000	6,100,000
Additional Paid-In Capital
Debt Instrument [Line Items]
Repurchase of junior convertible securities, equity impact	1,300,000	6,100,000
Junior convertible securities
Debt Instrument [Line Items]
Debt	$ 297,500,000	$ 297,500,000		$ 314,000,000
Junior Convertible Trust Preferred Securities \| Junior convertible securities
Debt Instrument [Line Items]
Debt interest rate	5.15%	5.15%
Debt	$ 301,400,000	$ 301,400,000
Face amount	$ 404,700,000	$ 404,700,000
Debt instrument, term		16 years
Repayments of long-term debt		$ 28,700,000
Repurchase of junior convertible securities, debt impact		26,100,000
Deferred tax liabilities, net, decrease resulting from repurchase of junior convertible securities		6,200,000
Junior Convertible Trust Preferred Securities \| Junior convertible securities \| Additional Paid-In Capital
Debt Instrument [Line Items]
Repurchase of junior convertible securities, equity impact		$ 6,100,000

Derivative Financial Instrume_3

Derivative Financial Instruments - Additional Information (Details) - USD ($)	3 Months Ended
	Mar. 31, 2020	Sep. 30, 2021	Dec. 31, 2020
Other assets
Derivative [Line Items]
Derivative assets, gross		$ 1,000,000	$ 3,500,000
Other liabilities
Derivative [Line Items]
Derivative liabilities, gross		2,500,000	$ 4,200,000
Foreign contracts and collar contracts
Derivative [Line Items]
Proceeds from derivative termination	$ 24,900,000
Forward foreign currency contracts
Derivative [Line Items]
Cash collateral held from counterparty		0
Cash collateral held at counterparty		$ 1,100,000
Designated as Hedging Instrument \| Cash Flow Hedging \| Interest rate swap
Derivative [Line Items]
Fixed interest rate		0.5135%
Derivative notional amount		$ 250,000,000

Derivative Financial Instrume_4

Derivative Financial Instruments - Assets and Liabilities Measured at Fair Value on Recurring Basis (Details) - Fair Value, Measurements, Recurring - Designated as Hedging Instrument - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Derivative [Line Items]
Assets	$ 1	$ 3.5
Liabilities	(2.5)	(4.2)
Net Investment Hedging \| Forward foreign currency contracts
Derivative [Line Items]
Assets	1	3.5
Liabilities	(1.4)	(2.3)
Cash Flow Hedging \| Interest rate swap
Derivative [Line Items]
Assets	0	0
Liabilities	$ (1.1)	$ (1.9)

Derivative Financial Instrume_5

Derivative Financial Instruments - Effect on Statement of Comprehensive Income and Statement of Income (Details) - Designated as Hedging Instrument - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Derivative [Line Items]
Gain (Loss) Recognized in Other Comprehensive Income	$ (1.9)	$ 0.3	$ (0.9)	$ 13.8
Gain Reclassified from Accumulated Other Comprehensive Loss into Earnings	0.4	0.1	1.4	0.4
Gain (Loss) Recognized in Earnings from Excluded Components	0	0	0	2.8
Forward foreign currency contracts \| Net Investment Hedging
Derivative [Line Items]
Gain (Loss) Recognized in Other Comprehensive Income	(2)	0.4	(1.6)	64.9
Gain Reclassified from Accumulated Other Comprehensive Loss into Earnings	0.4	0.1	1.4	0.4
Gain (Loss) Recognized in Earnings from Excluded Components	0	0	0	2.8
Put options \| Net Investment Hedging
Derivative [Line Items]
Gain (Loss) Recognized in Other Comprehensive Income			0	(47.7)
Gain Reclassified from Accumulated Other Comprehensive Loss into Earnings			0	0
Gain (Loss) Recognized in Earnings from Excluded Components			0	0
Call options \| Net Investment Hedging
Derivative [Line Items]
Gain (Loss) Recognized in Other Comprehensive Income			0	(1.3)
Gain Reclassified from Accumulated Other Comprehensive Loss into Earnings			0	0
Gain (Loss) Recognized in Earnings from Excluded Components			0	0
Interest rate swap \| Cash Flow Hedging
Derivative [Line Items]
Gain (Loss) Recognized in Other Comprehensive Income	0.1	(0.1)	0.7	(2.1)
Gain Reclassified from Accumulated Other Comprehensive Loss into Earnings	0	0	0	0
Gain (Loss) Recognized in Earnings from Excluded Components	$ 0	$ 0	$ 0	$ 0

Commitments and Contingencies (

Commitments and Contingencies (Details) - USD ($)	Oct. 01, 2021	Dec. 31, 2020	Sep. 30, 2021
Commitments and Contingencies
Co-investment commitments in partnership			$ 114,100,000
Parnassus \| Subsequent Event
Commitments and Contingencies
Payments to acquire businesses	$ 300,400,000
Consideration transferred, deferred	150,200,000
Contingent payment obligation (up to)	$ 75,100,000
Equity Method Investee
Commitments and Contingencies
Total contingent payments			103,900,000
Contingent payments in year one			$ 40,000,000
Noncontrolling interest, sell of ownership percentage		5.00%
Undisclosed Affiliate \| Equity Method Investee
Commitments and Contingencies
Ownership percentage by minority owner			14.00%
Payments for Achievement of Financial Targets
Commitments and Contingencies
Total contingent payments			$ 188,000,000
Contingent payments in year one			40,500,000
Contingent payments after year one			147,500,000
Expected payments			15,000,000
Payment contingent on not meeting financial targets (up to)			12,500,000
Payment contingent on exercise of option to reduce ownership percentage			$ 25,000,000

Goodwill and Acquired Client _3

Goodwill and Acquired Client Relationships - Schedule of Changes in Goodwill (Details) $ in Millions	9 Months Ended
	Sep. 30, 2021USD ($)
Goodwill [Roll Forward]
Beginning balance	$ 2,661.4
Foreign currency translation	(2.9)
Ending balance	$ 2,658.5

Goodwill and Acquired Client _4

Goodwill and Acquired Client Relationships - Schedule of Changes in the Components of Acquired Client Relationships (Details) - USD ($)	3 Months Ended			9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Jun. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Total
Beginning balance, net book value				$ 1,048,800,000
Intangible amortization and impairments	$ (8,900,000)	$ (31,900,000)		(25,300,000)	$ (133,400,000)
Ending balance, net book value	1,018,200,000			1,018,200,000
Acquired Client Relationships
Definite-lived
Beginning balance, gross book value				1,166,600,000
Beginning balance, accumulated amortization				(1,026,800,000)
Beginning balance, net book value				139,800,000
Intangible amortization and impairments				(25,300,000)
Foreign currency translation, gross				(200,000)
Foreign currency translation, accumulated amortization				100,000
Foreign currency translation, net				(100,000)
Ending balance, gross book value	1,166,400,000			1,166,400,000
Ending balance, accumulated amortization	(1,052,000,000)			(1,052,000,000)
Ending balance, net book value	114,400,000			114,400,000
Indefinite-lived
Beginning balance, net book value		$ 0		909,000,000
Intangible impairments			$ (60,300,000)	0
Foreign currency translation				(5,200,000)
Ending balance, net book value	903,800,000		$ 0	903,800,000
Total
Beginning balance, net book value				1,048,800,000
Intangible amortization and impairments				(25,300,000)
Foreign currency translation				(5,300,000)
Ending balance, net book value	$ 1,018,200,000			$ 1,018,200,000

Goodwill and Acquired Client _5

Goodwill and Acquired Client Relationships - Additional Information (Details) - USD ($)	3 Months Ended			9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Jun. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Acquired Client Relationships
Estimated Future Amortization Expense of Finite-Lived Intangibles
Intangible impairments		$ 14,000,000		$ 0
Average projected growth rate		(14.00%)
Discount rate for assets based fees		15.00%
Market participant tax rate		25.00%
Closure of Certain Retail Investment Products \| Acquired Client Relationships
Estimated Future Amortization Expense of Finite-Lived Intangibles
Intangible impairments		$ 10,900,000
Indefinite-lived acquired client relationships	$ 0			0
Controlling Interest \| Acquired Client Relationships
Estimated Future Amortization Expense of Finite-Lived Intangibles
Intangible impairments		12,500,000
Controlling Interest \| Closure of Certain Retail Investment Products \| Acquired Client Relationships
Estimated Future Amortization Expense of Finite-Lived Intangibles
Intangible impairments		7,400,000
Acquired Client Relationships
Intangible Assets
Amortization and impairment expenses of intangible assets				25,300,000
Estimated Future Amortization Expense of Finite-Lived Intangibles
Finite-lived intangible, future amortization expense, remainder of fiscal year	9,000,000			9,000,000
Finite-lived intangible, future amortization expense in year one	30,000,000			30,000,000
Finite-lived intangible, future amortization expense in year two	30,000,000			30,000,000
Finite-lived intangible, future amortization expense in year three	15,000,000			15,000,000
Finite-lived intangible, future amortization expense in year four	10,000,000			10,000,000
Finite-lived intangible, future amortization expense in year five	10,000,000			10,000,000
Intangible impairments			$ 60,300,000	0
Indefinite-lived acquired client relationships	903,800,000		0	903,800,000		$ 909,000,000
Acquired Client Relationships \| Controlling Interest
Estimated Future Amortization Expense of Finite-Lived Intangibles
Intangible impairments			$ 32,800,000
Acquired Client Relationships \| Intangible amortization and impairments
Intangible Assets
Amortization and impairment expenses of intangible assets	$ 8,900,000	$ 7,000,000		$ 25,300,000	$ 48,200,000

Equity Method Investments in _3

Equity Method Investments in Affiliates - Change in Equity Method Investments (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020
Change in Equity Method Investments in Affiliates [Roll Forward]
Balance, as of December 31, 2020	$ 2,074.8
Distributions of earnings	(288.1)	$ (197.2)
Return of capital	(3.4)	$ 0
Balance, as of September 30, 2021	2,085.2
Equity Method Investee
Change in Equity Method Investments in Affiliates [Roll Forward]
Balance, as of December 31, 2020	2,074.8
Investments in Affiliates	144.3
Earnings	218.9
Intangible amortization and impairments	(93.8)
Distributions of earnings	(288.1)
Return of capital	(3.4)
Foreign currency translation	25.8
Other	6.7
Balance, as of September 30, 2021	$ 2,085.2

Equity Method Investments in _4

Equity Method Investments in Affiliates - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended			9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Mar. 31, 2020	Sep. 30, 2021	Sep. 30, 2020
Acquired Client Relationships
Schedule of Equity Method Investments [Line Items]
Amortization of Intangible Assets				$ 25.3
Estimated Future Amortization Expense of Finite-Lived Intangibles
Finite-lived intangible, future amortization expense, remainder of fiscal year	$ 9			9
Finite-lived intangible, future amortization expense in year one	30			30
Finite-lived intangible, future amortization expense in year two	30			30
Finite-lived intangible, future amortization expense in year three	15			15
Finite-lived intangible, future amortization expense in year four	10			10
Finite-lived intangible, future amortization expense in year five	10			10
Equity Method Investee
Estimated Future Amortization Expense of Finite-Lived Intangibles
Impairment expense			$ 140
Average projected growth rate period			5 years
Average projected growth rate			(2.00%)
Discount rate for assets based fees			11.00%
Discount rate for performance fees			20.00%
Market participant tax rate			25.00%
Total contingent payments	103.9			103.9
Contingent payments in remainder of fiscal year	63.9			63.9
Contingent payments in year one	40			40
Equity Method Investee \| Acquired Client Relationships
Schedule of Equity Method Investments [Line Items]
Amortization of Intangible Assets	29.3	$ 34.3		93.8	$ 110.5
Estimated Future Amortization Expense of Finite-Lived Intangibles
Finite-lived intangible, future amortization expense, remainder of fiscal year	30			30
Finite-lived intangible, future amortization expense in year one	80			80
Finite-lived intangible, future amortization expense in year two	80			80
Finite-lived intangible, future amortization expense in year three	50			50
Finite-lived intangible, future amortization expense in year four	50			50
Finite-lived intangible, future amortization expense in year five	$ 50			$ 50

Related Party Transactions (Det

Related Party Transactions (Details) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Related Party Transactions
Other liabilities	$ 463.3	$ 452.2
Prior Owner \| Private Equity Investment Partnerships of Affiliate
Related Party Transactions
Other liabilities	$ 31.7	$ 35.4

Share-Based Compensation - Shar

Share-Based Compensation - Share-Based Compensation Expense (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Share-based Payment Arrangement [Abstract]
Share-based compensation	$ 21.2	$ 15.7	$ 44.5	$ 46.4
Tax benefit	3.5	$ 2.9	7.8	$ 8.4
Compensation expense related to share-based compensation	$ 82.5		$ 82.5		$ 86.2
Weighted average period over which compensation expense will be recognized			3 years

Share-Based Compensation - Rest

Share-Based Compensation - Restricted Stock Units Transactions (Details) - Restricted Stock Units - USD ($) $ / shares in Units, shares in Millions, $ in Millions	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020
Restricted Stock Units
Unvested units - beginning balance (in shares)	1.2
Units granted (in shares)	0.2
Units vested (in shares)	(0.3)
Units forfeited (in shares)	(0.1)
Performance condition changes (in shares)	0.1
Unvested units - ending balance (in shares)	1.1
Weighted Average Grant Date Value
Unvested units - beginning balance (in dollars per share)	$ 99.46
Units granted (in dollars per share)	139.71
Units vested (in dollars per share)	130.58
Units forfeited (in dollars per share)	105.45
Performance condition changes (in dollars per share)	80.19
Unvested units - ending balance (in dollars per share)	$ 94.22
Restricted stocks granted, fair value	$ 27.8	$ 31.6
Minimum
Weighted Average Grant Date Value
Restricted stock, vesting period	3 years
Maximum
Weighted Average Grant Date Value
Restricted stock, vesting period	4 years

Share-Based Compensation - Sche

Share-Based Compensation - Schedule of the Transactions of the Company's Stock Options (Details) shares in Millions	9 Months Ended
	Sep. 30, 2021$ / sharesshares
Stock Options
Unexercised options outstanding - beginning balance (in shares) \| shares	2.9
Options granted (in shares) \| shares	0
Options exercised (in shares) \| shares	(0.2)
Options forfeited (in shares) \| shares	0
Performance condition changes (in shares) \| shares	0.6
Unexercised options outstanding - ending balance (in shares) \| shares	3.3
Stock Options, Exercisable at the end of the period (in shares) \| shares	0.2
Weighted Average Exercise Price
Unexercised options outstanding - beginning balance (in dollars per share) \| $ / shares	$ 82.14
Options granted (in dollars per share) \| $ / shares	150.68
Options exercised (in dollars per share) \| $ / shares	120.12
Options forfeited (in dollars per share) \| $ / shares	154.44
Performance condition changes (in dollars per share) \| $ / shares	74.42
Unexercised options outstanding - ending balance (in dollars per share) \| $ / shares	78.21
Weighted Average Exercise Price, Exercisable at the end of the period (in dollars per share) \| $ / shares	$ 131.74
Weighted Average Remaining Contractual Life (Years)
Unexercised options outstanding at the end of the period	4 years 9 months 18 days
Exercisable at the end of the period	1 year 7 months 6 days

Share-Based Compensation - Fair

Share-Based Compensation - Fair Value Options Granted and Assumptions (Details) - USD ($) $ / shares in Units, $ in Millions	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020
Share-based Compensation
Stock options granted, fair value	$ 2	$ 4.4
Stock options granted, weighted average fair value (in dollars per share)	$ 54.19	$ 18.23
Stock Options
Share-based Compensation
Stock options, expiration period	7 years
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions and Methodology [Abstract]
Dividend yield	0.00%	1.60%
Expected volatility	37.10%	30.40%
Risk-free interest rate	1.00%	0.90%
Expected life of options (in years)	5 years 8 months 12 days	5 years 8 months 12 days
Forfeiture rate	0.00%	0.00%
Stock Options \| Minimum
Share-based Compensation
Stock options, vesting period	3 years
Stock Options \| Maximum
Share-based Compensation
Stock options, vesting period	5 years

Redeemable Non-Controlling In_3

Redeemable Non-Controlling Interests (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Redeemable Noncontrolling Interest [Roll Forward]
Balance, beginning balance			$ 671.5
Decrease attributable to consolidated Affiliate sponsored investment products			(17.1)
Transfers to Other liabilities			(86.3)
Transfers from Non-controlling interests	$ 0.1	$ 0.2	3.9	$ 5.6
Changes in redemption value	(0.9)	$ 50.7	176.9	$ 18.6
Balance, ending balance	748.9		$ 748.9
Minimum
Noncontrolling Interest [Line Items]
Term of conditional right to put interest			5 years
Maximum
Noncontrolling Interest [Line Items]
Term of conditional right to put interest			15 years
Variable Interest Entity, Primary Beneficiary
Redeemable Noncontrolling Interest [Roll Forward]
Balance, beginning balance			$ 35.4
Balance, ending balance	$ 18.3		$ 18.3

Affiliated Equity - Additional

Affiliated Equity - Additional Information (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Affiliate Equity [Line Items]
Distributions paid to affiliate partners	$ 260.9	$ 249.1
Payments to acquire interest in affiliates	65.9	249.6
Issuance of interest in affiliates	18.1	$ 17.1
Other assets
Affiliate Equity [Line Items]
Due from affiliates	15.5		$ 9.6
Other liabilities
Affiliate Equity [Line Items]
Due to affiliates	$ 47.7		$ 22

Affiliate Equity - Summary of A

Affiliate Equity - Summary of Affiliate Recognized and Unrecognized Expense (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Affiliate Equity [Line Items]
Affiliate equity compensation expense	$ 11.7	$ 9.5	$ 46.4	$ 36.3
Non- controlling Interests
Affiliate Equity [Line Items]
Non-controlling interests	8.9	6	$ 36.5	24.9
Unrecognized Affiliate Equity Expense [Abstract]
Remaining Life			4 years		5 years
Non-controlling Interests	108.1		$ 108.1		$ 109.7
Affiliated Entity
Affiliate Equity [Line Items]
Controlling interest	2.8	$ 3.5	9.9	$ 11.4
Unrecognized Affiliate Equity Expense [Abstract]
Controlling Interest	$ 47.6		$ 47.6		$ 35.9
Remaining Life			5 years		4 years

Affiliate Equity - Changes in t

Affiliate Equity - Changes in the Company's Interest in its Affiliates on the Controlling Interest's Equity (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Affiliate Equity [Abstract]
Net income (controlling interest)	$ 128.4	$ 71.3	$ 387.3	$ 86.3
Increase (decrease) in controlling interest paid-in capital from Affiliate equity issuances	0	2.9	(17.5)	1.6
Decrease in controlling interest paid-in capital from Affiliate equity purchases	(1.2)	(65.4)	(57.2)	(226)
Net income (loss) (controlling interest) including the net impact of Affiliate equity transactions	$ 127.2	$ 8.8	$ 312.6	$ (138.1)

Income Taxes - Schedule of Cons

Income Taxes - Schedule of Consolidated Provision for Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Income Tax Provision
Deferred taxes			$ 87.6	$ 10.6
Income tax expense	$ 44.9	$ 37.5	166.4	43
Non- controlling Interests
Income Tax Provision
Current taxes	2.3	3.1	7.2	7.4
Deferred taxes	0	1.9	6	1.9
Income tax expense	2.3	5	13.2	9.3
Controlling Interest
Income Tax Provision
Current taxes	23.2	4.4	71.6	25
Intangible-related deferred taxes	12	27	51.9	(7.1)
Other deferred taxes	7.4	1.1	29.7	15.8
Income tax expense	42.6	32.5	153.2	33.7
Income before income taxes (controlling interest)	$ 171	$ 103.8	$ 540.5	$ 120
Effective tax rate (controlling interests)	24.90%	31.30%	28.30%	28.10%

Income Taxes - Additional Infor

Income Taxes - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Income Tax Provision
Effective income tax rate reconciliation, change in enacted tax rate, amount	$ 8.1	$ 19.2	$ 8.1
Effective income tax rate reconciliation, nondeductible expense, share-based payment arrangement, amount			3.6
Effective income tax rate reconciliation, release of uncertain tax position			$ 5.5

Earnings Per Share - Schedule o

Earnings Per Share - Schedule of Basic and Diluted Earnings (Loss) Per Share (Details) - USD ($) shares in Millions, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Numerator
Net income (controlling interest)	$ 128.4	$ 71.3	$ 387.3	$ 86.3
Interest expense on junior convertible securities, net of taxes	4.6	0	13.9	0
Net income (controlling interest), as adjusted	$ 133	$ 71.3	$ 401.2	$ 86.3
Denominator
Average shares outstanding (basic) (in shares)	41.1	46.3	41.8	47.1
Effect of dilutive instruments:
Stock options and restricted stock units (in shares)	1.1	0.2	0.9	0.1
Junior convertible securities (in shares)	2.1	0	2.1	0
Average shares outstanding (diluted) (in shares)	44.3	46.5	44.8	47.2

Earnings Per Share - Schedule_2

Earnings Per Share - Schedule of Shares Excluded from Calculation of Basic and Diluted Earnings (Loss) Per Share (Details) - shares shares in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Stock options and restricted stock units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share (in shares)	0.1	2.9	0.2	3.1
Junior convertible securities
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share (in shares)	0	2.2	0	2.2

Earnings Per Share - Additional

Earnings Per Share - Additional Information (Details) - $ / shares shares in Millions	3 Months Ended	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2021
Earnings Per Share [Abstract]
Number or shares repurchased during period (in shares)	0.6	2.8
Average price of shares repurchased during period (in dollars per share)	$ 161.02	$ 141.58

Comprehensive Income - Summary

Comprehensive Income - Summary of the Tax Effects Allocated to Each Component of Other Comprehensive Income (Loss) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Accumulated Other Comprehensive Income (Loss)
Pre-Tax	$ (20.9)	$ 25.4	$ 17.7	$ (42.3)
Tax Expense	(0.7)	(0.5)	(7)	(11.2)
Other comprehensive income (loss), net of tax	(21.6)	24.9	10.7	(53.5)
Foreign currency translation gain (loss)
Accumulated Other Comprehensive Income (Loss)
Pre-Tax	(19)	25.2	18.6	(39.7)
Tax Expense	(0.7)	(0.5)	(6.9)	(11.7)
Other comprehensive income (loss), net of tax	(19.7)	24.7	11.7	(51.4)
Change in net realized and unrealized gain (loss) on derivative financial instruments
Accumulated Other Comprehensive Income (Loss)
Pre-Tax	(1.9)	0.2	(0.9)	(2.6)
Tax Expense	0	0	(0.1)	0.5
Other comprehensive income (loss), net of tax	$ (1.9)	$ 0.2	$ (1)	$ (2.1)

Comprehensive Income - Componen

Comprehensive Income - Components of AOCL (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Components of Accumulated other comprehensive income, net of taxes
Beginning balance	$ 3,157.9	$ 3,341.9	$ 3,317.3	$ 3,499.1
Other comprehensive income before reclassifications			12.1
Amounts reclassified			(1.4)
Other comprehensive income (loss), net of tax	(21.6)	24.9	10.7	(53.5)
Ending balance	3,199.5	3,328.4	3,199.5	3,328.4
Total
Components of Accumulated other comprehensive income, net of taxes
Beginning balance			(162.2)
Ending balance	(151.5)		(151.5)
Foreign Currency Translation Adjustment
Components of Accumulated other comprehensive income, net of taxes
Beginning balance			(161.9)
Other comprehensive income before reclassifications			11.7
Amounts reclassified			0
Other comprehensive income (loss), net of tax	(19.7)	24.7	11.7	(51.4)
Ending balance	(150.2)		(150.2)
Realized and Unrealized Gains (Losses) on Derivative Financial Instruments
Components of Accumulated other comprehensive income, net of taxes
Beginning balance			(0.3)
Other comprehensive income before reclassifications			0.4
Amounts reclassified			(1.4)
Other comprehensive income (loss), net of tax	(1.9)	$ 0.2	(1)	$ (2.1)
Ending balance	$ (1.3)		$ (1.3)