Public Service Co Of New Hampshire 10-Q3 May 242024 Q1 Quarterly reportFinancial data

Company Profile

COVER PAGE

COVER PAGE - shares	3 Months Ended
COVER PAGE - shares	Mar. 31, 2024	Apr. 30, 2024
Document And Entity [Line Items]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Mar. 31, 2024
Document Transition Report	false
Entity Registrant Name	EVERSOURCE ENERGY
Entity Incorporation, State or Country Code	MA
Entity Address, Address Line One	300 Cadwell Drive
Entity Address, City or Town	Springfield
Entity Address, State or Province	MA
Entity Address, Postal Zip Code	01104
City Area Code	800
Local Phone Number	286-5000
Entity File Number	001-05324
Entity Tax Identification Number	04-2147929
Title of 12(b) Security	Common Shares, $5.00 par value per share
Trading Symbol	ES
Security Exchange Name	NYSE
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Smaller Reporting Company	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding (in shares)		352,255,238
Entity Central Index Key	0000072741
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2024
Document Fiscal Period Focus	Q1
Amendment Flag	false
The Connecticut Light and Power Company
Document And Entity [Line Items]
Entity Registrant Name	THE CONNECTICUT LIGHT AND POWER COMPANY
Entity Incorporation, State or Country Code	CT
Entity Address, Address Line One	107 Selden Street
Entity Address, City or Town	Berlin
Entity Address, State or Province	CT
Entity Address, Postal Zip Code	06037-1616
City Area Code	800
Local Phone Number	286-5000
Entity File Number	000-00404
Entity Tax Identification Number	06-0303850
Entity Filer Category	Non-accelerated Filer
Entity Smaller Reporting Company	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding (in shares)		6,035,205
Entity Central Index Key	0000023426
Current Fiscal Year End Date	--12-31
NSTAR Electric Company
Document And Entity [Line Items]
Entity Registrant Name	NSTAR ELECTRIC COMPANY
Entity Incorporation, State or Country Code	MA
Entity Address, Address Line One	800 Boylston Street
Entity Address, City or Town	Boston
Entity Address, State or Province	MA
Entity Address, Postal Zip Code	02199
City Area Code	800
Local Phone Number	286-5000
Entity File Number	001-02301
Entity Tax Identification Number	04-1278810
Entity Filer Category	Non-accelerated Filer
Entity Smaller Reporting Company	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding (in shares)		200
Entity Central Index Key	0000013372
Current Fiscal Year End Date	--12-31
Public Service Company of New Hampshire
Document And Entity [Line Items]
Entity Registrant Name	PUBLIC SERVICE COMPANY OF NEW HAMPSHIRE
Entity Incorporation, State or Country Code	NH
Entity Address, Address Line One	Energy Park
Entity Address, Address Line Two	780 North Commercial Street
Entity Address, City or Town	Manchester
Entity Address, State or Province	NH
Entity Address, Postal Zip Code	03101-1134
City Area Code	800
Local Phone Number	286-5000
Entity File Number	001-06392
Entity Tax Identification Number	02-0181050
Entity Filer Category	Non-accelerated Filer
Entity Smaller Reporting Company	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding (in shares)		301
Entity Central Index Key	0000315256
Current Fiscal Year End Date	--12-31

CONDENSED CONSOLIDATED BALANCE

CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Current Assets:
Cash	$ 259,213	$ 53,873
Receivables, Net (net of allowance for uncollectible accounts)	1,593,487	1,431,531
Unbilled Revenues	195,594	225,325
Materials, Supplies, Natural Gas and REC Inventory	555,211	507,307
Regulatory Assets	1,889,499	1,674,196
Prepayments and Other Current Assets	387,854	355,762
Total Current Assets	4,880,858	4,247,994
Property, Plant and Equipment, Net	40,289,378	39,498,607
Deferred Debits and Other Assets:
Regulatory Assets	4,839,271	4,714,970
Goodwill	4,532,135	4,532,100
Investments in Unconsolidated Affiliates	741,697	660,473
Prepaid Pension and PBOP	1,085,121	1,028,207
Marketable Securities	334,293	337,814
Other Long-Term Assets	619,472	592,080
Total Deferred Debits and Other Assets	12,151,989	11,865,644
Total Assets	57,322,225	55,612,245
Current Liabilities:
Notes Payable	2,102,871	1,930,422
Long-Term Debt – Current Portion	865,374	824,847
Rate Reduction Bonds – Current Portion	43,210	43,210
Accounts Payable	1,663,661	1,869,187
Regulatory Liabilities	641,472	591,750
Other Current Liabilities	1,050,998	1,081,981
Total Current Liabilities	6,367,586	6,341,397
Deferred Credits and Other Liabilities:
Accumulated Deferred Income Taxes	5,314,688	5,303,730
Regulatory Liabilities	4,051,377	4,022,923
Asset Retirement Obligations	506,040	505,844
Accrued Pension, SERP and PBOP	124,035	123,754
Other Long-Term Liabilities	983,853	1,029,238
Total Deferred Credits and Other Liabilities	10,979,993	10,985,489
Long-Term Debt	24,929,813	23,588,616
Rate Reduction Bonds	345,677	367,282
Noncontrolling Interest – Preferred Stock of Subsidiaries	155,568	155,569
Common Shareholders' Equity:
Common Shares	1,806,385	1,799,920
Capital Surplus, Paid In	8,537,591	8,460,876
Retained Earnings	4,413,593	4,142,515
Accumulated Other Comprehensive Loss	(28,534)	(33,737)
Treasury Stock	(185,447)	(195,682)
Common Shareholders' Equity	14,543,588	14,173,892
Commitments and Contingencies
Total Liabilities and Capitalization	$ 57,322,225	$ 55,612,245

CONDENSED CONSOLIDATED BALANC_2

CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Statement of Financial Position [Abstract]
Allowance for uncollectible accounts	$ 570,134	$ 554,455

CONDENSED CONSOLIDATED STATEMEN

CONDENSED CONSOLIDATED STATEMENTS OF INCOME - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Income Statement [Abstract]
Operating Revenues	$ 3,332,575	$ 3,795,643
Operating Expenses:
Purchased Power, Purchased Natural Gas and Transmission	1,235,956	1,903,246
Operations and Maintenance	462,964	454,562
Depreciation	339,914	312,955
Amortization	(2,325)	(76,059)
Energy Efficiency Programs	213,479	222,952
Taxes Other Than Income Taxes	236,614	228,414
Total Operating Expenses	2,486,602	3,046,070
Operating Income/(Loss)	845,973	749,573
Interest Expense	250,749	194,543
Other Income, Net	91,030	88,981
Income Before Income Tax Expense	686,254	644,011
Income Tax Expense	162,526	150,972
Net Income	523,728	493,039
Net Income Attributable to Noncontrolling Interests	1,880	1,880
Net Income Attributable to Common Shareholders	$ 521,848	$ 491,159
Basic EPS (in dollars per share)	$ 1.49	$ 1.41
Diluted EPS (in dollars per share)	$ 1.49	$ 1.41
Weighted Average Common Shares Outstanding:
Basic (in shares)	350,717,114	349,217,147
Diluted (in shares)	350,997,220	349,612,013

CONDENSED CONSOLIDATED STATEM_2

CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Statement of Comprehensive Income [Abstract]
Net Income	$ 523,728	$ 493,039
Other Comprehensive Income, Net of Tax:
Qualified Cash Flow Hedging Instruments	5	5
Changes in Unrealized Gains on Marketable Securities	0	1,254
Changes in Funded Status of Pension, SERP and PBOP Benefit Plans	5,198	1,971
Other Comprehensive Income, Net of Tax	5,203	3,230
Comprehensive Income Attributable to Noncontrolling Interests	(1,880)	(1,880)
Comprehensive Income Attributable to Common Shareholders	$ 527,051	$ 494,389

CONDENSED CONSOLIDATED STATEM_3

CONDENSED CONSOLIDATED STATEMENTS OF COMMON SHAREHOLDERS' EQUITY - USD ($) $ in Thousands	Total	Common Shares	Capital Surplus, Paid In	Retained Earnings	Accumulated Other Comprehensive Loss	Treasury Stock
Balance (in shares) at Dec. 31, 2022		348,443,855
Balance at Dec. 31, 2022	$ 15,473,158	$ 1,799,920	$ 8,401,731	$ 5,527,153	$ (39,421)	$ (216,225)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income	493,039			493,039
Dividends on Common Stock	(235,354)			(235,354)
Dividends on Preferred Stock	(1,880)			(1,880)
Long-Term Incentive Plan Activity	(13,141)		(13,141)
Issuance of Treasury Shares (in shares)		364,227
Issuance of Treasury Shares	30,319		23,495			6,824
Other Comprehensive Income, Net of Tax	3,230				3,230
Balance (in shares) at Mar. 31, 2023		348,808,082
Balance at Mar. 31, 2023	$ 15,749,371	$ 1,799,920	8,412,085	5,782,958	(36,191)	(209,401)
Balance (in shares) at Dec. 31, 2023	349,540,266	349,540,266
Balance at Dec. 31, 2023	$ 14,173,892	$ 1,799,920	8,460,876	4,142,515	(33,737)	(195,682)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income	523,728			523,728
Dividends on Common Stock	(250,770)			(250,770)
Dividends on Preferred Stock	(1,880)			(1,880)
Issuance of Common Shares (in shares)		1,292,892
Issuance of Common Shares	76,437	$ 6,465	69,972
Long-Term Incentive Plan Activity	(22,405)		(22,405)
Issuance of Treasury Shares (in shares)		546,256
Issuance of Treasury Shares	40,425		30,190			10,235
Capital Stock Expense	(1,042)		(1,042)
Other Comprehensive Income, Net of Tax	$ 5,203				5,203
Balance (in shares) at Mar. 31, 2024	351,379,414	351,379,414
Balance at Mar. 31, 2024	$ 14,543,588	$ 1,806,385	$ 8,537,591	$ 4,413,593	$ (28,534)	$ (185,447)

CONDENSED CONSOLIDATED STATEM_4

CONDENSED CONSOLIDATED STATEMENTS OF COMMON SHAREHOLDERS' EQUITY (Parenthetical) - $ / shares	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Statement of Stockholders' Equity [Abstract]
Dividends on Common Shares (in dollars per share)	$ 0.715	$ 0.675
Par value (in dollars per share)	$ 5

CONDENSED CONSOLIDATED STATEM_5

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Operating Activities:
Net Income	$ 523,728	$ 493,039
Adjustments to Reconcile Net Income to Net Cash Flows Provided by/(Used In) Operating Activities:
Depreciation	339,914	312,955
Deferred Income Taxes	156,976	149,197
Uncollectible Expense	16,387	22,821
Pension, SERP and PBOP Income, Net	(16,938)	(24,563)
Pension Contributions	(1,250)	(1,100)
Regulatory Under Recoveries, Net	(232,350)	(158,964)
Amortization	(2,325)	(76,059)
Cost of Removal Expenditures	(57,337)	(70,514)
Other	(58,687)	(54,486)
Changes in Current Assets and Liabilities:
Receivables and Unbilled Revenues, Net	(212,171)	(225,609)
Taxes Receivable/Accrued, Net	65,641	284
Accounts Payable	(107,014)	(258,476)
Other Current Assets and Liabilities, Net	(123,262)	(39,368)
Net Cash Flows Provided by/(Used In) Operating Activities	291,312	69,157
Investing Activities:
Investments in Property, Plant and Equipment	(1,149,443)	(977,144)
Proceeds from Sales of Marketable Securities	41,729	64,307
Purchases of Marketable Securities	(37,555)	(56,508)
Investments in Unconsolidated Affiliates	(307,433)	(87,845)
Other Investing Activities	5,850	5,640
Net Cash Flows Used in Investing Activities	(1,446,852)	(1,051,550)
Financing Activities:
Issuance of Common Shares, Net of Issuance Costs	75,395	0
Cash Dividends on Common Shares	(244,786)	(229,405)
Cash Dividends on Preferred Stock	(1,880)	(1,880)
Increase/(Decrease) in Notes Payable	216,119	(246,700)
Repayment of Rate Reduction Bonds	(21,605)	(21,605)
Issuance of Long-Term Debt	1,350,000	1,550,000
Retirement of Long-Term Debt	0	(400,000)
Other Financing Activities	(23,725)	(27,002)
Net Cash Flows Provided by/(Used In) Financing Activities	1,349,518	623,408
Net Increase/(Decrease) in Cash and Restricted Cash	193,978	(358,985)
Cash and Restricted Cash - Beginning of Period	166,418	521,752
Cash and Restricted Cash - End of Period	$ 360,396	$ 162,767

THE CONNECTICUT LIGHT AND POWER

THE CONNECTICUT LIGHT AND POWER COMPANY CONDENSED BALANCE SHEETS - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Current Assets:
Cash	$ 259,213	$ 53,873
Receivables, Net (net of allowance for uncollectible accounts)	1,593,487	1,431,531
Unbilled Revenues	195,594	225,325
Materials, Supplies and REC Inventory	555,211	507,307
Regulatory Assets	1,889,499	1,674,196
Prepayments and Other Current Assets	387,854	355,762
Total Current Assets	4,880,858	4,247,994
Property, Plant and Equipment, Net	40,289,378	39,498,607
Deferred Debits and Other Assets:
Regulatory Assets	4,839,271	4,714,970
Prepaid Pension and PBOP	1,085,121	1,028,207
Other Long-Term Assets	619,472	592,080
Total Deferred Debits and Other Assets	12,151,989	11,865,644
Total Assets	57,322,225	55,612,245
Current Liabilities:
Long-Term Debt – Current Portion	865,374	824,847
Accounts Payable	1,663,661	1,869,187
Regulatory Liabilities	641,472	591,750
Other Current Liabilities	1,050,998	1,081,981
Total Current Liabilities	6,367,586	6,341,397
Deferred Credits and Other Liabilities:
Accumulated Deferred Income Taxes	5,314,688	5,303,730
Regulatory Liabilities	4,051,377	4,022,923
Other Long-Term Liabilities	983,853	1,029,238
Total Deferred Credits and Other Liabilities	10,979,993	10,985,489
Long-Term Debt	24,929,813	23,588,616
Preferred Stock Not Subject to Mandatory Redemption	155,568	155,569
Common Shareholders' Equity:
Capital Surplus, Paid In	8,537,591	8,460,876
Retained Earnings	4,413,593	4,142,515
Accumulated Other Comprehensive Income	(28,534)	(33,737)
Common Shareholders' Equity	14,543,588	14,173,892
Commitments and Contingencies
Total Liabilities and Capitalization	57,322,225	55,612,245
The Connecticut Light and Power Company
Current Assets:
Cash	29,006	10,213
Unbilled Revenues	50,625	57,403
Materials, Supplies and REC Inventory	177,258	156,467
Regulatory Assets	717,608	480,369
Prepayments and Other Current Assets	89,317	94,789
Total Current Assets	1,741,042	1,418,684
Property, Plant and Equipment, Net	12,532,477	12,340,192
Deferred Debits and Other Assets:
Regulatory Assets	1,710,091	1,662,778
Prepaid Pension and PBOP	138,609	129,801
Other Long-Term Assets	318,942	298,169
Total Deferred Debits and Other Assets	2,167,642	2,090,748
Total Assets	16,441,161	15,849,624
Current Liabilities:
Notes Payable to Eversource Parent	426,100	249,670
Long-Term Debt – Current Portion	139,845	0
Obligations to Third Party Suppliers	70,037	75,753
Regulatory Liabilities	117,335	102,239
Derivative Liabilities	79,197	81,944
Other Current Liabilities	166,265	127,703
Total Current Liabilities	1,729,790	1,394,090
Deferred Credits and Other Liabilities:
Accumulated Deferred Income Taxes	1,960,837	1,860,122
Regulatory Liabilities	1,333,875	1,315,928
Other Long-Term Liabilities	241,293	258,185
Total Deferred Credits and Other Liabilities	3,536,005	3,434,235
Long-Term Debt	4,814,040	4,814,429
Preferred Stock Not Subject to Mandatory Redemption	116,200	116,200
Common Shareholders' Equity:
Common Stock	60,352	60,352
Capital Surplus, Paid In	3,484,265	3,384,265
Retained Earnings	2,700,331	2,645,868
Accumulated Other Comprehensive Income	178	185
Common Shareholders' Equity	6,245,126	6,090,670
Commitments and Contingencies
Total Liabilities and Capitalization	16,441,161	15,849,624
The Connecticut Light and Power Company \| Nonrelated Party
Current Assets:
Receivables, Net (net of allowance for uncollectible accounts)	586,642	558,993
Current Liabilities:
Accounts Payable	579,695	622,055
The Connecticut Light and Power Company \| Related Party
Current Assets:
Receivables, Net (net of allowance for uncollectible accounts)	90,586	60,450
Current Liabilities:
Notes Payable to Eversource Parent	426,100	457,000
Accounts Payable	$ 151,316	134,726
Deferred Credits and Other Liabilities:
Long-Term Debt		$ 207,300

THE CONNECTICUT LIGHT AND POW_2

THE CONNECTICUT LIGHT AND POWER COMPANY CONDENSED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Allowance for uncollectible accounts	$ 570,134	$ 554,455
The Connecticut Light and Power Company
Allowance for uncollectible accounts	$ 307,834	$ 296,030

THE CONNECTICUT LIGHT AND POW_3

THE CONNECTICUT LIGHT AND POWER COMPANY CONDENSED STATEMENTS OF INCOME - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Operating Revenues	$ 3,332,575	$ 3,795,643
Operating Expenses:
Purchased Power and Transmission	1,235,956	1,903,246
Operations and Maintenance	462,964	454,562
Depreciation	339,914	312,955
Energy Efficiency Programs	213,479	222,952
Taxes Other Than Income Taxes	236,614	228,414
Total Operating Expenses	2,486,602	3,046,070
Operating Income/(Loss)	845,973	749,573
Interest Expense	250,749	194,543
Other Income, Net	91,030	88,981
Income Before Income Tax Expense	686,254	644,011
Income Tax Expense	162,526	150,972
The Connecticut Light and Power Company
Operating Revenues	1,121,291	1,338,905
Operating Expenses:
Purchased Power and Transmission	565,996	850,564
Operations and Maintenance	186,764	160,316
Depreciation	98,445	92,237
Amortization of Regulatory Liabilities, Net	(91,713)	(122,315)
Energy Efficiency Programs	35,600	32,646
Taxes Other Than Income Taxes	103,801	101,584
Total Operating Expenses	898,893	1,115,032
Operating Income/(Loss)	222,398	223,873
Interest Expense	54,824	45,201
Other Income, Net	16,468	14,937
Income Before Income Tax Expense	184,042	193,609
Income Tax Expense	45,689	45,193
Net Income	$ 138,353	$ 148,416

THE CONNECTICUT LIGHT AND POW_4

THE CONNECTICUT LIGHT AND POWER COMPANY CONDENSED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Other Comprehensive (Loss)/Income, Net of Tax:
Comprehensive Income Attributable to Common Shareholders	$ 527,051	$ 494,389
The Connecticut Light and Power Company
Net Income	138,353	148,416
Other Comprehensive (Loss)/Income, Net of Tax:
Qualified Cash Flow Hedging Instruments	(7)	(7)
Changes in Unrealized Gains on Marketable Securities	0	43
Other Comprehensive Income, Net of Tax	(7)	36
Comprehensive Income Attributable to Common Shareholders	$ 138,346	$ 148,452

THE CONNECTICUT LIGHT AND POW_5

THE CONNECTICUT LIGHT AND POWER COMPANY CONDENSED STATEMENTS OF COMMON STOCKHOLDER'S EQUITY - USD ($) $ in Thousands	Total	Common Stock	Capital Surplus, Paid In	Retained Earnings	Accumulated Other Comprehensive Loss	The Connecticut Light and Power Company	The Connecticut Light and Power Company Common Stock	The Connecticut Light and Power Company Capital Surplus, Paid In	The Connecticut Light and Power Company Retained Earnings	The Connecticut Light and Power Company Accumulated Other Comprehensive Loss
Balance (in shares) at Dec. 31, 2022		348,443,855					6,035,205
Balance at Dec. 31, 2022	$ 15,473,158	$ 1,799,920	$ 8,401,731	$ 5,527,153	$ (39,421)	$ 5,784,380	$ 60,352	$ 3,260,765	$ 2,463,094	$ 169
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income						148,416			148,416
Dividends on Preferred Stock	(1,880)			(1,880)		(1,390)			(1,390)
Dividends on Common Stock	(235,354)			(235,354)		(82,600)			(82,600)
Other Comprehensive Income (Loss)						36				36
Balance (in shares) at Mar. 31, 2023		348,808,082					6,035,205
Balance at Mar. 31, 2023	$ 15,749,371	$ 1,799,920	8,412,085	5,782,958	(36,191)	5,848,842	$ 60,352	3,260,765	2,527,520	205
Balance (in shares) at Dec. 31, 2023	349,540,266	349,540,266					6,035,205
Balance at Dec. 31, 2023	$ 14,173,892	$ 1,799,920	8,460,876	4,142,515	(33,737)	6,090,670	$ 60,352	3,384,265	2,645,868	185
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income						138,353			138,353
Dividends on Preferred Stock	(1,880)			(1,880)		(1,390)			(1,390)
Dividends on Common Stock	$ (250,770)			(250,770)		(82,500)			(82,500)
Capital Contributions from Eversource Parent						100,000		100,000
Other Comprehensive Income (Loss)						(7)				(7)
Balance (in shares) at Mar. 31, 2024	351,379,414	351,379,414					6,035,205
Balance at Mar. 31, 2024	$ 14,543,588	$ 1,806,385	$ 8,537,591	$ 4,413,593	$ (28,534)	$ 6,245,126	$ 60,352	$ 3,484,265	$ 2,700,331	$ 178

THE CONNECTICUT LIGHT AND POW_6

THE CONNECTICUT LIGHT AND POWER COMPANY CONDENSED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Adjustments to Reconcile Net Income to Net Cash Flows Provided by/(Used In) Operating Activities:
Depreciation	$ 339,914	$ 312,955
Deferred Income Taxes	156,976	149,197
Uncollectible Expense	16,387	22,821
Pension, SERP, and PBOP Income, Net	(16,938)	(24,563)
Regulatory Under Recoveries, Net	(232,350)	(158,964)
Cost of Removal Expenditures	(57,337)	(70,514)
Other	(58,687)	(54,486)
Changes in Current Assets and Liabilities:
Receivables and Unbilled Revenues, Net	(212,171)	(225,609)
Taxes Receivable/Accrued, Net	65,641	284
Accounts Payable	(107,014)	(258,476)
Other Current Assets and Liabilities, Net	(123,262)	(39,368)
Net Cash Flows Provided by/(Used In) Operating Activities	291,312	69,157
Investing Activities:
Investments in Property, Plant and Equipment	(1,149,443)	(977,144)
Other Investing Activities	5,850	5,640
Net Cash Flows Used in Investing Activities	(1,446,852)	(1,051,550)
Financing Activities:
Cash Dividends on Common Stock	(244,786)	(229,405)
Cash Dividends on Preferred Stock	(1,880)	(1,880)
Issuance of Long-Term Debt	1,350,000	1,550,000
Retirement of Long-Term Debt	0	(400,000)
Increase/(Decrease) in Notes Payable to Eversource Parent	216,119	(246,700)
Other Financing Activities	(23,725)	(27,002)
Net Cash Flows Provided by/(Used In) Financing Activities	1,349,518	623,408
Net Increase/(Decrease) in Cash and Restricted Cash	193,978	(358,985)
Cash and Restricted Cash - Beginning of Period	166,418	521,752
Cash and Restricted Cash - End of Period	360,396	162,767
The Connecticut Light and Power Company
Operating Activities:
Net Income	138,353	148,416
Adjustments to Reconcile Net Income to Net Cash Flows Provided by/(Used In) Operating Activities:
Depreciation	98,445	92,237
Deferred Income Taxes	91,630	94,267
Uncollectible Expense	3,507	3,876
Pension, SERP, and PBOP Income, Net	(3,557)	(4,461)
Regulatory Under Recoveries, Net	(139,979)	(110,114)
Amortization of Regulatory Liabilities, Net	(91,713)	(122,315)
Cost of Removal Expenditures	(17,675)	(13,011)
Other	(32,174)	(13,964)
Changes in Current Assets and Liabilities:
Receivables and Unbilled Revenues, Net	(80,396)	(76,482)
Taxes Receivable/Accrued, Net	66,015	52,261
Accounts Payable	(20,613)	(110,926)
Other Current Assets and Liabilities, Net	(38,466)	(13,412)
Net Cash Flows Provided by/(Used In) Operating Activities	(26,623)	(73,628)
Investing Activities:
Investments in Property, Plant and Equipment	(285,888)	(255,905)
Other Investing Activities	0	126
Net Cash Flows Used in Investing Activities	(285,888)	(255,779)
Financing Activities:
Cash Dividends on Common Stock	(82,500)	(82,600)
Cash Dividends on Preferred Stock	(1,390)	(1,390)
Capital Contributions from Eversource Parent	100,000	0
Issuance of Long-Term Debt	350,000	500,000
Retirement of Long-Term Debt	0	(400,000)
Increase/(Decrease) in Notes Payable to Eversource Parent	(30,900)	318,000
Other Financing Activities	(3,887)	(6,521)
Net Cash Flows Provided by/(Used In) Financing Activities	331,323	327,489
Net Increase/(Decrease) in Cash and Restricted Cash	18,812	(1,918)
Cash and Restricted Cash - Beginning of Period	12,243	20,327
Cash and Restricted Cash - End of Period	$ 31,055	$ 18,409

NSTAR ELECTRIC COMPANY AND SUBS

NSTAR ELECTRIC COMPANY AND SUBSIDIARY CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Current Assets:
Cash	$ 259,213	$ 53,873
Receivables, Net (net of allowance for uncollectible accounts)	1,593,487	1,431,531
Unbilled Revenues	195,594	225,325
Materials, Supplies and REC Inventory	555,211	507,307
Regulatory Assets	1,889,499	1,674,196
Prepayments and Other Current Assets	387,854	355,762
Total Current Assets	4,880,858	4,247,994
Property, Plant and Equipment, Net	40,289,378	39,498,607
Deferred Debits and Other Assets:
Regulatory Assets	4,839,271	4,714,970
Prepaid Pension and PBOP	1,085,121	1,028,207
Other Long-Term Assets	619,472	592,080
Total Deferred Debits and Other Assets	12,151,989	11,865,644
Total Assets	57,322,225	55,612,245
Current Liabilities:
Notes Payable	2,102,871	1,930,422
Accounts Payable	1,663,661	1,869,187
Regulatory Liabilities	641,472	591,750
Other Current Liabilities	1,050,998	1,081,981
Total Current Liabilities	6,367,586	6,341,397
Deferred Credits and Other Liabilities:
Accumulated Deferred Income Taxes	5,314,688	5,303,730
Regulatory Liabilities	4,051,377	4,022,923
Other Long-Term Liabilities	983,853	1,029,238
Total Deferred Credits and Other Liabilities	10,979,993	10,985,489
Long-Term Debt	24,929,813	23,588,616
Preferred Stock Not Subject to Mandatory Redemption	155,568	155,569
Common Shareholders' Equity:
Capital Surplus, Paid In	8,537,591	8,460,876
Retained Earnings	4,413,593	4,142,515
Accumulated Other Comprehensive Income	(28,534)	(33,737)
Common Shareholders' Equity	14,543,588	14,173,892
Commitments and Contingencies
Total Liabilities and Capitalization	57,322,225	55,612,245
NSTAR Electric Company
Current Assets:
Cash	20,226	6,740
Unbilled Revenues	47,999	49,897
Materials, Supplies and REC Inventory	210,993	173,770
Regulatory Assets	718,726	676,083
Prepayments and Other Current Assets	65,926	41,464
Total Current Assets	1,684,094	1,510,295
Property, Plant and Equipment, Net	13,040,321	12,753,787
Deferred Debits and Other Assets:
Regulatory Assets	1,322,249	1,281,836
Prepaid Pension and PBOP	629,131	608,617
Other Long-Term Assets	125,196	116,978
Total Deferred Debits and Other Assets	2,076,576	2,007,431
Total Assets	16,800,991	16,271,513
Current Liabilities:
Notes Payable	419,000	365,847
Obligations to Third Party Suppliers	162,414	139,823
Renewable Portfolio Standards Compliance Obligations	142,193	116,010
Regulatory Liabilities	405,190	368,070
Other Current Liabilities	86,460	84,688
Total Current Liabilities	1,917,118	1,818,756
Deferred Credits and Other Liabilities:
Accumulated Deferred Income Taxes	1,892,041	1,849,613
Regulatory Liabilities	1,603,079	1,585,311
Other Long-Term Liabilities	334,530	327,388
Total Deferred Credits and Other Liabilities	3,829,650	3,762,312
Long-Term Debt	4,497,954	4,496,947
Preferred Stock Not Subject to Mandatory Redemption	43,000	43,000
Common Shareholders' Equity:
Common Stock	0	0
Capital Surplus, Paid In	3,313,842	3,013,842
Retained Earnings	3,199,399	3,136,612
Accumulated Other Comprehensive Income	28	44
Common Shareholders' Equity	6,513,269	6,150,498
Commitments and Contingencies
Total Liabilities and Capitalization	16,800,991	16,271,513
NSTAR Electric Company \| Nonrelated Party
Current Assets:
Receivables, Net (net of allowance for uncollectible accounts)	545,961	487,707
Current Liabilities:
Accounts Payable	486,110	599,696
NSTAR Electric Company \| Related Party
Current Assets:
Receivables, Net (net of allowance for uncollectible accounts)	74,263	74,634
Current Liabilities:
Accounts Payable	$ 215,751	$ 144,622

NSTAR ELECTRIC COMPANY AND SU_2

NSTAR ELECTRIC COMPANY AND SUBSIDIARY CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Allowance for uncollectible accounts	$ 570,134	$ 554,455
NSTAR Electric
Allowance for uncollectible accounts	$ 97,653	$ 97,026

NSTAR ELECTRIC COMPANY AND SU_3

NSTAR ELECTRIC COMPANY AND SUBSIDIARY CONDENSED CONSOLIDATED STATEMENTS OF INCOME - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Operating Revenues	$ 3,332,575	$ 3,795,643
Operating Expenses:
Purchased Power and Transmission	1,235,956	1,903,246
Operations and Maintenance	462,964	454,562
Depreciation	339,914	312,955
Energy Efficiency Programs	213,479	222,952
Taxes Other Than Income Taxes	236,614	228,414
Total Operating Expenses	2,486,602	3,046,070
Operating Income/(Loss)	845,973	749,573
Interest Expense	250,749	194,543
Other Income, Net	91,030	88,981
Income Before Income Tax Expense	686,254	644,011
Income Tax Expense	162,526	150,972
NSTAR Electric Company
Operating Revenues	947,615	956,283
Operating Expenses:
Purchased Power and Transmission	273,305	360,925
Operations and Maintenance	173,672	166,083
Depreciation	96,922	90,430
Amortization of Regulatory Liabilities, Net	48,392	22,785
Energy Efficiency Programs	82,301	86,217
Taxes Other Than Income Taxes	60,010	53,510
Total Operating Expenses	734,602	779,950
Operating Income/(Loss)	213,013	176,333
Interest Expense	49,423	44,865
Other Income, Net	47,114	39,873
Income Before Income Tax Expense	210,704	171,341
Income Tax Expense	50,727	37,528
Net Income	$ 159,977	$ 133,813

NSTAR ELECTRIC COMPANY AND SU_4

NSTAR ELECTRIC COMPANY AND SUBSIDIARY CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Other Comprehensive Income, Net of Tax:
Comprehensive Income Attributable to Common Shareholders	$ 527,051	$ 494,389
NSTAR Electric Company
Net Income	159,977	133,813
Other Comprehensive Income, Net of Tax:
Changes in Funded Status of SERP Benefit Plan	(21)	(33)
Qualified Cash Flow Hedging Instruments	5	5
Changes in Unrealized Gains on Marketable Securities	0	12
Other Comprehensive Income, Net of Tax	(16)	(16)
Comprehensive Income Attributable to Common Shareholders	$ 159,961	$ 133,797

NSTAR ELECTRIC COMPANY AND SU_5

NSTAR ELECTRIC COMPANY AND SUBSIDIARY CONDENSED CONSOLIDATED STATEMENTS OF COMMON STOCKHOLDER'S EQUITY - USD ($) $ in Thousands	Total	Common Stock	Capital Surplus, Paid In	Retained Earnings	Accumulated Other Comprehensive Loss	NSTAR Electric	NSTAR Electric Common Stock	NSTAR Electric Capital Surplus, Paid In	NSTAR Electric Retained Earnings	NSTAR Electric Accumulated Other Comprehensive Loss
Balance (in shares) at Dec. 31, 2022		348,443,855					200
Balance at Dec. 31, 2022	$ 15,473,158	$ 1,799,920	$ 8,401,731	$ 5,527,153	$ (39,421)	$ 5,700,670	$ 0	$ 2,778,942	$ 2,921,444	$ 284
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income						133,813			133,813
Dividends on Preferred Stock	(1,880)			(1,880)		(490)			(490)
Dividends on Common Stock	(235,354)			(235,354)		(327,400)			(327,400)
Capital Contributions from Eversource Parent						31,300		31,300
Other Comprehensive Income (Loss)						(16)				(16)
Balance (in shares) at Mar. 31, 2023		348,808,082					200
Balance at Mar. 31, 2023	$ 15,749,371	$ 1,799,920	8,412,085	5,782,958	(36,191)	5,537,877	$ 0	2,810,242	2,727,367	268
Balance (in shares) at Dec. 31, 2023	349,540,266	349,540,266					200
Balance at Dec. 31, 2023	$ 14,173,892	$ 1,799,920	8,460,876	4,142,515	(33,737)	6,150,498	$ 0	3,013,842	3,136,612	44
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income						159,977			159,977
Dividends on Preferred Stock	(1,880)			(1,880)		(490)			(490)
Dividends on Common Stock	$ (250,770)			(250,770)		(96,700)			(96,700)
Capital Contributions from Eversource Parent						300,000		300,000
Other Comprehensive Income (Loss)						(16)				(16)
Balance (in shares) at Mar. 31, 2024	351,379,414	351,379,414					200
Balance at Mar. 31, 2024	$ 14,543,588	$ 1,806,385	$ 8,537,591	$ 4,413,593	$ (28,534)	$ 6,513,269	$ 0	$ 3,313,842	$ 3,199,399	$ 28

NSTAR ELECTRIC COMPANY AND SU_6

NSTAR ELECTRIC COMPANY AND SUBSIDIARY CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Adjustments to Reconcile Net Income to Net Cash Flows Provided by/(Used In) Operating Activities:
Depreciation	$ 339,914	$ 312,955
Deferred Income Taxes	156,976	149,197
Uncollectible Expense	16,387	22,821
Pension, SERP and PBOP Income, Net	(16,938)	(24,563)
Regulatory Under Recoveries, Net	(232,350)	(158,964)
Cost of Removal Expenditures	(57,337)	(70,514)
Other	(58,687)	(54,486)
Changes in Current Assets and Liabilities:
Receivables and Unbilled Revenues, Net	(212,171)	(225,609)
Taxes Receivable/Accrued, Net	65,641	284
Accounts Payable	(107,014)	(258,476)
Other Current Assets and Liabilities, Net	(123,262)	(39,368)
Net Cash Flows Provided by/(Used In) Operating Activities	291,312	69,157
Investing Activities:
Investments in Property, Plant and Equipment	(1,149,443)	(977,144)
Other Investing Activities	5,850	5,640
Net Cash Flows Used in Investing Activities	(1,446,852)	(1,051,550)
Financing Activities:
Cash Dividends on Common Stock	(244,786)	(229,405)
Cash Dividends on Preferred Stock	(1,880)	(1,880)
Other Financing Activities	(23,725)	(27,002)
Net Cash Flows Provided by/(Used In) Financing Activities	1,349,518	623,408
Net Increase/(Decrease) in Cash and Restricted Cash	193,978	(358,985)
Cash and Restricted Cash - Beginning of Period	166,418	521,752
Cash and Restricted Cash - End of Period	360,396	162,767
NSTAR Electric
Operating Activities:
Net Income	159,977	133,813
Adjustments to Reconcile Net Income to Net Cash Flows Provided by/(Used In) Operating Activities:
Depreciation	96,922	90,430
Deferred Income Taxes	31,812	44,403
Uncollectible Expense	6,109	4,697
Pension, SERP and PBOP Income, Net	(8,954)	(9,886)
Regulatory Under Recoveries, Net	(85,422)	(58,000)
Amortization of Regulatory Assets/(Liabilities), Net	48,392	22,785
Cost of Removal Expenditures	(11,715)	(12,893)
Other	(12,395)	(9,921)
Changes in Current Assets and Liabilities:
Receivables and Unbilled Revenues, Net	(74,262)	(90,684)
Taxes Receivable/Accrued, Net	(18,223)	11,977
Accounts Payable	13,088	20,249
Other Current Assets and Liabilities, Net	7,316	(6,185)
Net Cash Flows Provided by/(Used In) Operating Activities	152,645	140,785
Investing Activities:
Investments in Property, Plant and Equipment	(394,895)	(318,673)
Other Investing Activities	0	35
Net Cash Flows Used in Investing Activities	(394,895)	(318,638)
Financing Activities:
Cash Dividends on Common Stock	(96,700)	(327,400)
Cash Dividends on Preferred Stock	(490)	(490)
Capital Contributions from Eversource Parent	300,000	31,300
Increase in Notes Payable	53,153	147,500
Other Financing Activities	5	5
Net Cash Flows Provided by/(Used In) Financing Activities	255,968	(149,085)
Net Increase/(Decrease) in Cash and Restricted Cash	13,718	(326,938)
Cash and Restricted Cash - Beginning of Period	22,785	345,293
Cash and Restricted Cash - End of Period	$ 36,503	$ 18,355

PUBLIC SERVICE COMPANY OF NEW H

PUBLIC SERVICE COMPANY OF NEW HAMPSHIRE AND SUBSIDIARIES CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Current Assets:
Cash	$ 259,213	$ 53,873
Receivables, Net (net of allowance for uncollectible accounts)	1,593,487	1,431,531
Unbilled Revenues	195,594	225,325
Materials, Supplies and REC Inventory	555,211	507,307
Regulatory Assets	1,889,499	1,674,196
Prepayments	387,854	355,762
Total Current Assets	4,880,858	4,247,994
Property, Plant and Equipment, Net	40,289,378	39,498,607
Deferred Debits and Other Assets:
Regulatory Assets	4,839,271	4,714,970
Prepaid Pension and PBOP	1,085,121	1,028,207
Other Long-Term Assets	619,472	592,080
Total Deferred Debits and Other Assets	12,151,989	11,865,644
Total Assets	57,322,225	55,612,245
Current Liabilities:
Rate Reduction Bonds – Current Portion	43,210	43,210
Accounts Payable	1,663,661	1,869,187
Regulatory Liabilities	641,472	591,750
Other Current Liabilities	1,050,998	1,081,981
Total Current Liabilities	6,367,586	6,341,397
Deferred Credits and Other Liabilities:
Accumulated Deferred Income Taxes	5,314,688	5,303,730
Regulatory Liabilities	4,051,377	4,022,923
Other Long-Term Liabilities	983,853	1,029,238
Total Deferred Credits and Other Liabilities	10,979,993	10,985,489
Long-Term Debt	24,929,813	23,588,616
Rate Reduction Bonds	345,677	367,282
Common Shareholders' Equity:
Capital Surplus, Paid In	8,537,591	8,460,876
Retained Earnings	4,413,593	4,142,515
Common Shareholders' Equity	14,543,588	14,173,892
Commitments and Contingencies
Total Liabilities and Capitalization	57,322,225	55,612,245
PSNH
Current Assets:
Cash	14,067	240
Unbilled Revenues	45,108	55,012
Taxes Receivable	33,534	27,146
Materials, Supplies and REC Inventory	79,846	77,066
Regulatory Assets	188,057	189,450
Special Deposits	17,065	31,586
Prepayments	5,291	18,489
Total Current Assets	551,027	569,479
Property, Plant and Equipment, Net	4,707,625	4,574,652
Deferred Debits and Other Assets:
Regulatory Assets	811,457	773,783
Prepaid Pension and PBOP	64,019	58,979
Other Long-Term Assets	16,062	16,558
Total Deferred Debits and Other Assets	891,538	849,320
Total Assets	6,150,190	5,993,451
Current Liabilities:
Notes Payable to Eversource Parent	0	233,000
Rate Reduction Bonds – Current Portion	43,210	43,210
Regulatory Liabilities	86,141	117,515
Other Current Liabilities	63,096	72,328
Total Current Liabilities	463,127	713,069
Deferred Credits and Other Liabilities:
Accumulated Deferred Income Taxes	724,212	691,532
Regulatory Liabilities	389,427	393,574
Other Long-Term Liabilities	42,793	42,484
Total Deferred Credits and Other Liabilities	1,156,432	1,127,590
Long-Term Debt	1,682,679	1,431,591
Rate Reduction Bonds	345,677	367,282
Common Shareholders' Equity:
Common Stock	0	0
Capital Surplus, Paid In	1,798,134	1,698,134
Retained Earnings	704,141	655,785
Common Shareholders' Equity	2,502,275	2,353,919
Commitments and Contingencies
Total Liabilities and Capitalization	6,150,190	5,993,451
PSNH \| Nonrelated Party
Current Assets:
Receivables, Net (net of allowance for uncollectible accounts)	146,327	152,276
Current Liabilities:
Accounts Payable	212,844	205,744
PSNH \| Related Party
Current Assets:
Receivables, Net (net of allowance for uncollectible accounts)	21,732	18,214
Current Liabilities:
Notes Payable to Eversource Parent	251,000	233,000
Accounts Payable	57,836	$ 41,272
Deferred Credits and Other Liabilities:
Long-Term Debt	$ 251,000

PUBLIC SERVICE COMPANY OF NEW_2

PUBLIC SERVICE COMPANY OF NEW HAMPSHIRE AND SUBSIDIARIES CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Allowance for uncollectible accounts	$ 570,134	$ 554,455
PSNH
Allowance for uncollectible accounts	$ 13,812	$ 14,322

PUBLIC SERVICE COMPANY OF NEW_3

PUBLIC SERVICE COMPANY OF NEW HAMPSHIRE AND SUBSIDIARIES CONDENSED CONSOLIDATED STATEMENTS OF INCOME - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Operating Revenues	$ 3,332,575	$ 3,795,643
Operating Expenses:
Purchased Power and Transmission	1,235,956	1,903,246
Operations and Maintenance	462,964	454,562
Depreciation	339,914	312,955
Energy Efficiency Programs	213,479	222,952
Taxes Other Than Income Taxes	236,614	228,414
Total Operating Expenses	2,486,602	3,046,070
Operating Income/(Loss)	845,973	749,573
Interest Expense	250,749	194,543
Other Income, Net	91,030	88,981
Income Before Income Tax Expense	686,254	644,011
Income Tax Expense	162,526	150,972
PSNH
Operating Revenues	326,116	420,155
Operating Expenses:
Purchased Power and Transmission	87,938	226,685
Operations and Maintenance	68,712	67,796
Depreciation	37,409	34,088
Amortization of Regulatory Liabilities, Net	21,264	(5,317)
Energy Efficiency Programs	11,176	10,226
Taxes Other Than Income Taxes	23,316	22,105
Total Operating Expenses	249,815	355,583
Operating Income/(Loss)	76,301	64,572
Interest Expense	19,194	17,542
Other Income, Net	7,050	5,717
Income Before Income Tax Expense	64,157	52,747
Income Tax Expense	15,801	12,451
Net Income	$ 48,356	$ 40,296

PUBLIC SERVICE COMPANY OF NEW_4

PUBLIC SERVICE COMPANY OF NEW HAMPSHIRE AND SUBSIDIARIES CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Other Comprehensive (Loss)/Income, Net of Tax:
Comprehensive Income Attributable to Common Shareholders	$ 527,051	$ 494,389
PSNH
Net Income	48,356	40,296
Other Comprehensive (Loss)/Income, Net of Tax:
Changes in Unrealized Gains on Marketable Securities	0	73
Other Comprehensive Income, Net of Tax	0	73
Comprehensive Income Attributable to Common Shareholders	$ 48,356	$ 40,369

PUBLIC SERVICE COMPANY OF NEW_5

PUBLIC SERVICE COMPANY OF NEW HAMPSHIRE AND SUBSIDIARIES CONDENSED CONSOLIDATED STATEMENTS OF COMMON STOCKHOLDER'S EQUITY - USD ($) $ in Thousands	Total	Common Stock	Capital Surplus, Paid In	Retained Earnings	Accumulated Other Comprehensive Loss	PSNH	PSNH Common Stock	PSNH Capital Surplus, Paid In	PSNH Retained Earnings	PSNH Accumulated Other Comprehensive Loss
Balance (in shares) at Dec. 31, 2022		348,443,855					301
Balance at Dec. 31, 2022	$ 15,473,158	$ 1,799,920	$ 8,401,731	$ 5,527,153	$ (39,421)	$ 1,870,187	$ 0	$ 1,298,134	$ 572,126	$ (73)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income						40,296			40,296
Dividends on Common Stock	(235,354)			(235,354)		(28,000)			(28,000)
Other Comprehensive Income (Loss)						73				73
Balance (in shares) at Mar. 31, 2023		348,808,082					301
Balance at Mar. 31, 2023	$ 15,749,371	$ 1,799,920	8,412,085	5,782,958	(36,191)	1,882,556	$ 0	1,298,134	584,422	0
Balance (in shares) at Dec. 31, 2023	349,540,266	349,540,266					301
Balance at Dec. 31, 2023	$ 14,173,892	$ 1,799,920	8,460,876	4,142,515	(33,737)	2,353,919	$ 0	1,698,134	655,785	0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income						48,356			48,356
Dividends on Common Stock	$ (250,770)			(250,770)
Capital Contributions from Eversource Parent						100,000		100,000
Other Comprehensive Income (Loss)						0
Balance (in shares) at Mar. 31, 2024	351,379,414	351,379,414					301
Balance at Mar. 31, 2024	$ 14,543,588	$ 1,806,385	$ 8,537,591	$ 4,413,593	$ (28,534)	$ 2,502,275	$ 0	$ 1,798,134	$ 704,141	$ 0

PUBLIC SERVICE COMPANY OF NEW_6

PUBLIC SERVICE COMPANY OF NEW HAMPSHIRE AND SUBSIDIARIES CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Adjustments to Reconcile Net Income to Net Cash Flows Provided by/(Used In) Operating Activities:
Depreciation	$ 339,914	$ 312,955
Deferred Income Taxes	156,976	149,197
Uncollectible Expense	16,387	22,821
Pension, SERP and PBOP Income, Net	(16,938)	(24,563)
Regulatory Under Recoveries, Net	(232,350)	(158,964)
Cost of Removal Expenditures	(57,337)	(70,514)
Other	(58,687)	(54,486)
Changes in Current Assets and Liabilities:
Receivables and Unbilled Revenues, Net	(212,171)	(225,609)
Taxes Receivable/Accrued, Net	65,641	284
Accounts Payable	(107,014)	(258,476)
Other Current Assets and Liabilities, Net	(123,262)	(39,368)
Net Cash Flows Provided by/(Used In) Operating Activities	291,312	69,157
Investing Activities:
Investments in Property, Plant and Equipment	(1,149,443)	(977,144)
Other Investing Activities	5,850	5,640
Net Cash Flows Used in Investing Activities	(1,446,852)	(1,051,550)
Financing Activities:
Cash Dividends on Common Shares	(244,786)	(229,405)
Issuance of Long-Term Debt	1,350,000	1,550,000
Repayment of Rate Reduction Bonds	(21,605)	(21,605)
Increase/(Decrease) in Notes Payable to Eversource Parent	216,119	(246,700)
Other Financing Activities	(23,725)	(27,002)
Net Cash Flows Provided by/(Used In) Financing Activities	1,349,518	623,408
Net Increase/(Decrease) in Cash and Restricted Cash	193,978	(358,985)
Cash and Restricted Cash - Beginning of Period	166,418	521,752
Cash and Restricted Cash - End of Period	360,396	162,767
PSNH
Operating Activities:
Net Income	48,356	40,296
Adjustments to Reconcile Net Income to Net Cash Flows Provided by/(Used In) Operating Activities:
Depreciation	37,409	34,088
Deferred Income Taxes	31,763	62,924
Uncollectible Expense	1,163	5,060
Pension, SERP and PBOP Income, Net	(2,322)	(2,552)
Regulatory Under Recoveries, Net	(78,464)	(175,865)
Amortization of Regulatory Assets/(Liabilities), Net	21,264	(5,317)
Cost of Removal Expenditures	(12,518)	(4,508)
Other	761	1,711
Changes in Current Assets and Liabilities:
Receivables and Unbilled Revenues, Net	11,194	(21,230)
Taxes Receivable/Accrued, Net	(6,387)	(20,195)
Accounts Payable	(1,559)	10,265
Other Current Assets and Liabilities, Net	1,186	2,462
Net Cash Flows Provided by/(Used In) Operating Activities	51,846	(72,861)
Investing Activities:
Investments in Property, Plant and Equipment	(148,934)	(133,890)
Other Investing Activities	0	216
Net Cash Flows Used in Investing Activities	(148,934)	(133,674)
Financing Activities:
Cash Dividends on Common Shares	0	(28,000)
Capital Contributions from Eversource Parent	100,000	0
Issuance of Long-Term Debt	0	300,000
Repayment of Rate Reduction Bonds	(21,605)	(21,605)
Increase/(Decrease) in Notes Payable to Eversource Parent	18,000	(52,200)
Other Financing Activities	0	(5,460)
Net Cash Flows Provided by/(Used In) Financing Activities	96,395	192,735
Net Increase/(Decrease) in Cash and Restricted Cash	(693)	(13,800)
Cash and Restricted Cash - Beginning of Period	35,004	36,812
Cash and Restricted Cash - End of Period	$ 34,311	$ 23,012

SUMMARY OF SIGNIFICANT ACCOUNTI

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	3 Months Ended
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	Mar. 31, 2024
Accounting Policies [Abstract]
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES A. Basis of Presentation Eversource Energy is a public utility holding company primarily engaged, through its wholly-owned regulated utility subsidiaries, in the energy delivery business. Eversource Energy's wholly-owned regulated utility subsidiaries consist of CL&P, NSTAR Electric and PSNH (electric utilities), Yankee Gas, NSTAR Gas and EGMA (natural gas utilities), and Aquarion (water utilities). Eversource provides energy delivery and/or water service to approximately 4.4 million electric, natural gas and water customers through twelve regulated utilities in Connecticut, Massachusetts and New Hampshire. The unaudited condensed consolidated financial statements of Eversource, NSTAR Electric and PSNH include the accounts of each of their respective subsidiaries. Intercompany transactions have been eliminated in consolidation. The accompanying unaudited condensed consolidated financial statements of Eversource, NSTAR Electric and PSNH and the unaudited condensed financial statements of CL&P are herein collectively referred to as the "financial statements." The combined notes to the financial statements have been prepared pursuant to the rules and regulations of the SEC. Certain information and footnote disclosures included in annual financial statements prepared in accordance with GAAP have been omitted pursuant to such rules and regulations. The accompanying financial statements should be read in conjunction with the Combined Notes to Financial Statements included in Item 8, "Financial Statements and Supplementary Data," of the Eversource 2023 Form 10-K, which was filed with the SEC on February 14, 2024. The preparation of the financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and the disclosure of contingent liabilities as of the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates. The financial statements contain, in the opinion of management, all adjustments (including normal, recurring adjustments) necessary to present fairly Eversource's, CL&P's, NSTAR Electric's and PSNH's financial position as of March 31, 2024 and December 31, 2023, and the results of operations, comprehensive income, common shareholders' equity and cash flows for the three months ended March 31, 2024 and 2023. The results of operations, comprehensive income and cash flows for the three months ended March 31, 2024 and 2023 are not necessarily indicative of the results expected for a full year. CYAPC and YAEC are inactive regional nuclear power companies engaged in the long-term storage of their spent nuclear fuel. Eversource consolidates the operations of CYAPC and YAEC because CL&P's, NSTAR Electric's and PSNH's combined ownership and voting interests in each of these entities is greater than 50 percent. Intercompany transactions between CL&P, NSTAR Electric, PSNH and the CYAPC and YAEC companies have been eliminated in consolidation of the Eversource financial statements. Eversource holds several equity ownership interests that are not consolidated and are accounted for under the equity method, including 50 percent ownership interests in three offshore wind projects and a tax equity investment in one of the projects. See Note 1E, "Summary of Significant Accounting Policies – Investments in Unconsolidated Affiliates," for further information on Eversource’s equity method investments. Eversource's utility subsidiaries' electric, natural gas and water distribution and transmission businesses are subject to rate-regulation that is based on cost recovery and meets the criteria for application of accounting guidance for entities with rate-regulated operations, which considers the effect of regulation on the differences in the timing of the recognition of certain revenues and expenses from those of other businesses and industries. See Note 2, "Regulatory Accounting," for further information. Certain reclassifications of prior period data were made in the accompanying financial statements to conform to the current period presentation. B. Allowance for Uncollectible Accounts Receivables, Net on the balance sheets primarily includes trade receivables from retail customers and customers related to wholesale transmission contracts, wholesale market sales, sales of RECs, and property rentals. Receivables, Net also includes customer receivables for the purchase of electricity from a competitive third party supplier, the current portion of customer energy efficiency loans, property damage receivables and other miscellaneous receivables. There is no material concentration of receivables. Receivables are recorded at amortized cost, net of a credit loss provision (or allowance for uncollectible accounts). The current expected credit loss (CECL) model is applied to receivables for purposes of calculating the allowance for uncollectible accounts. This model is based on expected losses and results in the recognition of estimated expected credit losses, including uncollectible amounts for both billed and unbilled revenues, over the life of the receivable at the time a receivable is recorded. The allowance for uncollectible accounts is determined based upon a variety of judgments and factors, including an aging-based quantitative assessment that applies an estimated uncollectible percentage to each receivable aging category. Factors in determining credit loss include historical collection, write-off experience, analysis of delinquency statistics, and management's assessment of collectability from customers, including current economic conditions, customer payment trends, the impact on customer bills because of energy usage trends and changes in rates, flexible payment plans and financial hardship arrearage management programs offered to customers, reasonable forecasts, and expectations of future collectability and collection efforts. Management continuously assesses the collectability of receivables and adjusts estimates based on actual experience and future expectations based on economic conditions, collection efforts and other factors. Management also monitors the aging analysis of receivables to determine if there are changes in the collections of accounts receivable. Receivable balances are written off against the allowance for uncollectible accounts when the customer accounts are no longer in service and these balances are deemed to be uncollectible. Management concluded that the reserve balance as of March 31, 2024 adequately reflected the collection risk and net realizable value for its receivables. The PURA allows CL&P and Yankee Gas to accelerate the recovery of accounts receivable balances attributable to qualified customers under financial or medical duress (uncollectible hardship accounts receivable) outstanding for greater than 180 days and 90 days, respectively. The DPU allows NSTAR Electric, NSTAR Gas and EGMA to recover in rates amounts associated with certain uncollectible hardship accounts receivable. These uncollectible hardship customer account balances are included in Regulatory Assets or Other Long-Term Assets on the balance sheets. Hardship customers are protected from shut-off in certain circumstances, and historical collection experience has reflected a higher default risk as compared to the rest of the receivable population. Management uses a higher credit risk profile for this pool of trade receivables as compared to non-hardship receivables. The allowance for uncollectible hardship accounts is included in the total uncollectible allowance balance. The total allowance for uncollectible accounts is included in Receivables, Net on the balance sheets. The activity in the allowance for uncollectible accounts by portfolio segment as of March 31 st is as follows: Eversource CL&P NSTAR Electric PSNH (Millions of Dollars) Hardship Accounts Retail (Non-Hardship), Total Allowance Hardship Accounts Retail (Non-Hardship), Total Allowance Hardship Accounts Retail (Non-Hardship), Total Allowance Total Allowance Three Months Ended 2024 Beginning Balance $ 366.8 $ 187.7 $ 554.5 $ 259.7 $ 36.3 $ 296.0 $ 43.6 $ 53.4 $ 97.0 $ 14.3 Uncollectible Expense — 16.4 16.4 — 3.5 3.5 — 6.1 6.1 1.2 Uncollectible Costs Deferred (1) 27.5 11.4 38.9 22.7 2.7 25.4 (0.8) 4.4 3.6 1.3 Write-Offs (15.1) (28.5) (43.6) (10.8) (7.7) (18.5) (1.0) (9.2) (10.2) (3.2) Recoveries Collected 0.2 3.7 3.9 0.2 1.2 1.4 — 1.2 1.2 0.2 Ending Balance $ 379.4 $ 190.7 $ 570.1 $ 271.8 $ 36.0 $ 307.8 $ 41.8 $ 55.9 $ 97.7 $ 13.8 Eversource CL&P NSTAR Electric PSNH (Millions of Dollars) Hardship Accounts Retail (Non-Hardship), Total Allowance Hardship Accounts Retail (Non-Hardship), Total Allowance Hardship Accounts Retail (Non-Hardship), Total Allowance Total Allowance Three Months Ended 2023 Beginning Balance $ 284.4 $ 201.9 $ 486.3 $ 188.9 $ 36.4 $ 225.3 $ 43.7 $ 51.3 $ 95.0 $ 29.2 Uncollectible Expense — 22.8 22.8 — 3.9 3.9 — 4.7 4.7 5.1 Uncollectible Costs Deferred (1) 43.7 14.3 58.0 34.3 2.7 37.0 (1.3) 5.4 4.1 1.2 Write-Offs (9.7) (26.3) (36.0) (7.3) (7.0) (14.3) (0.4) (10.3) (10.7) (2.2) Recoveries Collected 0.3 3.7 4.0 0.3 1.2 1.5 — 1.5 1.5 0.2 Ending Balance $ 318.7 $ 216.4 $ 535.1 $ 216.2 $ 37.2 $ 253.4 $ 42.0 $ 52.6 $ 94.6 $ 33.5 (1) These expected credit losses are deferred as regulatory costs on the balance sheets, as these amounts are ultimately recovered in rates. Amounts include uncollectible costs for hardship accounts and other customer receivables, including uncollectible amounts related to uncollectible energy supply costs and COVID-19. C. Fair Value Measurements Fair value measurement guidance is applied to derivative contracts that are not elected or designated as "normal purchases" or "normal sales" (normal) and to marketable securities held in trusts. Fair value measurement guidance is also applied to valuations of the investments used to calculate the funded status of pension and PBOP plans, the nonrecurring fair value measurements of nonfinancial assets such as goodwill, long-lived assets, equity method investments, AROs, and in the valuation of business combinations and asset acquisitions. The fair value measurement guidance was also applied in estimating the fair value of preferred stock, long-term debt and RRBs. Fair Value Hierarchy: In measuring fair value, Eversource uses observable market data when available in order to minimize the use of unobservable inputs. Inputs used in fair value measurements are categorized into three fair value hierarchy levels for disclosure purposes. The entire fair value measurement is categorized based on the lowest level of input that is significant to the fair value measurement. Eversource evaluates the classification of assets and liabilities measured at fair value on a quarterly basis. The levels of the fair value hierarchy are described below: Level 1 - Inputs are quoted prices (unadjusted) in active markets for identical assets or liabilities as of the reporting date. Active markets are those in which transactions for the asset or liability occur in sufficient frequency and volume to provide pricing information on an ongoing basis. Level 2 - Inputs are quoted prices for similar instruments in active markets, quoted prices for identical or similar instruments in markets that are not active, and model-derived valuations in which all significant inputs are observable. Level 3 - Quoted market prices are not available. Fair value is derived from valuation techniques in which one or more significant inputs or assumptions are unobservable. Where possible, valuation techniques incorporate observable market inputs that can be validated to external sources such as industry exchanges, including prices of energy and energy-related products. Uncategorized - Investments that are measured at net asset value are not categorized within the fair value hierarchy. Determination of Fair Value: The valuation techniques and inputs used in Eversource's fair value measurements are described in Note 4, "Derivative Instruments," Note 5, "Marketable Securities," and Note 10, "Fair Value of Financial Instruments," to the financial statements. D. Other Income, Net The components of Other Income, Net on the statements of income were as follows: For the Three Months Ended March 31, 2024 March 31, 2023 (Millions of Dollars) Eversource CL&P NSTAR Electric PSNH Eversource CL&P NSTAR Electric PSNH Pension, SERP and PBOP Non-Service $ 27.8 $ 6.5 $ 12.3 $ 3.6 $ 34.8 $ 9.5 $ 14.7 $ 4.2 AFUDC Equity 26.8 6.0 16.2 1.9 15.5 4.1 9.5 0.7 Equity in Earnings of Unconsolidated Affiliates 7.8 — 0.2 — 3.8 — 0.1 — Investment (Loss)/Income (0.8) (0.7) 0.4 (0.2) (1.7) (0.6) (0.5) (0.1) Interest Income 30.0 4.7 18.0 1.8 23.1 1.9 16.0 0.9 Other (1) (0.6) — — — 13.5 — 0.1 — Total Other Income, Net $ 91.0 $ 16.5 $ 47.1 $ 7.1 $ 89.0 $ 14.9 $ 39.9 $ 5.7 (1) Eversource’s equity method investment in a renewable energy fund was liquidated in March 2023. Liquidation proceeds in excess of the carrying value were recorded in 2023 within Other in the table above. See Note 1E, "Summary of Significant Accounting Policies - Investments in Unconsolidated Affiliates," for further information. E. Investments in Unconsolidated Affiliates Investments in entities that are not consolidated are included in long-term assets on the balance sheets and earnings impacts from these equity investments are included in Other Income, Net on the statements of income. Eversource's investments included the following: Investment Balance (Millions of Dollars) Ownership Interest As of March 31, 2024 As of December 31, 2023 Offshore Wind Business 50% - 100% $ 596.4 $ 515.5 Natural Gas Pipeline - Algonquin Gas Transmission, LLC 15% 115.9 116.0 Other various 29.4 29.0 Total Investments in Unconsolidated Affiliates $ 741.7 $ 660.5 Offshore Wind Business: Eversource’s offshore wind business includes 50 percent ownership interests in each of North East Offshore and South Fork Class B Member, LLC, which collectively hold three offshore wind projects. North East Offshore holds the Revolution Wind project and the Sunrise Wind project. South Fork Class B Member, LLC holds the South Fork Wind project. Eversource’s offshore wind business also includes a noncontrolling tax equity investment in South Fork Wind through a 100 percent ownership in South Fork Wind Holdings, LLC Class A shares. The offshore wind projects are being developed and constructed through joint and equal partnerships with Ørsted. On May 25, 2023, Eversource announced that it had completed a strategic review of its offshore wind investments and determined that it would pursue the sale of its offshore wind investments. On September 7, 2023, Eversource completed the sale of its 50 percent interest in an uncommitted lease area consisting of approximately 175,000 developable acres located 25 miles off the south coast of Massachusetts to Ørsted for $625 million in an all-cash transaction. In September of 2023, Eversource made a contribution of $528 million using the proceeds from the lease area sale to invest in a tax equity interest for South Fork Wind. South Fork Wind was restructured as a tax equity investment, with Eversource purchasing 100 percent ownership of a new Class A tax equity membership interest. As a result of this investment, Eversource expects to receive approximately $400 million of investment tax credits (ITC) after the turbines are placed in service for South Fork Wind and meet the requirements to qualify for the ITC, in addition to other expected future cash flow benefits that aggregate to approximately $100 million. These investment tax credits will be utilized to reduce Eversource’s federal tax liability or generate tax refunds in future periods through 2026. As of March 31, 2024, six South Fork Wind turbines met the requirements to qualify for the investment tax credits. As a result, $193 million of expected investment tax credits were reclassified from the South Fork Wind tax equity investment balance reported in Investments in Unconsolidated Affiliates as a reduction in current taxes payable of $54 million and an increase in deferred tax assets of $139 million on the Eversource balance sheet as of March 31, 2024. An additional $37 million deferred tax asset was established through a reduction of the tax equity investment balance due to a temporary difference on the related depreciable property as of March 31, 2024. These balance sheet reclassifications represent non-cash transactions. Expected Sales of Offshore Wind Investments : On January 24, 2024, Ørsted signed an agreement with Eversource to acquire Eversource’s 50 percent share of Sunrise Wind, subject to the successful selection of Sunrise Wind in the New York fourth solicitation for offshore wind capacity, signing of an OREC contract with NYSERDA, finalization of agreements including the equity and asset purchase agreement, receipt of the final approval by BOEM of the Sunrise Wind Construction and Operations Plan (COP), and relevant regulatory approvals. On January 25, 2024, Sunrise Wind submitted a proposal in the New York fourth offshore wind solicitation and was selected by NYSERDA on February 29, 2024 for contract negotiation. Sunrise Wind is currently negotiating an OREC contract with NYSERDA that will include the price proposed by Sunrise Wind in the solicitation. We expect the OREC contract to be finalized in the second quarter of 2024. On April 18, 2024, Eversource and Ørsted executed the equity and asset purchase agreement to sell Eversource’s 50 percent interest in Sunrise Wind to Ørsted, and upon closing, Ørsted will become the sole owner of Sunrise Wind. Eversource will remain contracted to manage Sunrise Wind’s onshore construction through completion. In accordance with the equity and asset purchase agreement, Ørsted will pay Eversource 50 percent of the negotiated purchase price upon closing the sale transaction, with the remaining 50 percent paid after onshore construction is completed and certain other milestones are achieved. Upon the closing of the transaction, Eversource will not have any ongoing ownership interest in the project, nor any ongoing financial or credit support obligations associated with project costs. The impact of the purchase price from the sale of Sunrise Wind to Ørsted, as compared to the current carrying value of the investment which had assumed an abandonment of the project, will be reflected when the sale of Sunrise Wind is completed. In accordance with accounting guidance, the impairment loss recognized on the Sunrise Wind investment cannot subsequently be reversed for increases in estimated fair value, and therefore the impact will be recognized when the sale occurs. Eversource expects the sale of Sunrise Wind to Ørsted will be completed later this year. On February 13, 2024, Eversource announced that it executed an agreement to sell its existing 50 percent interests in the South Fork Wind and Revolution Wind projects to Global Infrastructure Partners (GIP). As part of this transaction, Eversource expects to receive approximately $1.1 billion of cash proceeds upon closing, which includes the sales value related to the 10 percent energy community ITC adder of approximately $170 million related to Revolution Wind, and to exit these projects while retaining certain cost sharing obligations for the construction of Revolution Wind. The purchase price is subject to future post-closing adjustment payments based on, among other things, the progress, timing and expense of construction of each project. The cost sharing obligations provide that Eversource would share equally with GIP in GIP’s funding obligations for up to approximately $240 million of incremental capital expenditure overruns incurred during the construction phase for the Revolution Wind project, after which obligations for any additional capital expenditure overruns would be shared equally by Eversource and Ørsted. Additionally, Eversource’s financial exposure will be adjusted by certain purchase price adjustments to be made following commercial operation of the Revolution Wind project and closing of South Fork as a result of final project economics, which includes Eversource’s obligation to maintain GIP’s internal rate of return for each project as specified in the agreement. South Fork Wind construction has been completed and Eversource does not expect any material cost sharing or other purchase price adjustment payments for South Fork Wind. Factors that could result in Eversource’s total net proceeds from the transaction to be lower or higher include Revolution Wind’s eligibility for federal investment tax credits at other than the anticipated 40 percent level; the ultimate cost of construction and extent of cost overruns for Revolution Wind; delays in constructing Revolution Wind, which would impact the economics associated with the purchase price adjustment; and a benefit due to Eversource if there are lower operation costs or higher availability of the projects through the period that is four years following the commercial operation date of the Revolution Wind project. Closing the transaction with GIP is subject to customary conditions, including certain regulatory approvals by the New York Public Service Commission, the FERC, and a review under the Hart Scott Rodino Act, as well as other conditions, among which is the completion and execution of the partnership agreements between GIP and Ørsted that will govern GIP’s new ownership interest in those projects following Eversource’s divestiture. The review period under the Hart Scott Rodino Act has expired. Closing of this transaction is currently expected to occur later this year. If closing of the sale is delayed, additional capital contributions made by Eversource would be recovered in the sales price. Under this agreement with GIP, Eversource’s existing credit support obligations are expected to roll off for each project around the time that each project completes its expected capital spend. Eversource will continue to make future cash expenditures for required cash contributions to its offshore wind investments up to the time of disposition of each of the offshore wind projects. Capital contributions are expected until the sales are completed and changes in the timing and amounts of these contributions would be adjusted in the sales prices and therefore not result in an additional impairment charge. Proceeds from the transactions will be used to pay off parent company debt. Impairment: Equity method investments are assessed for impairment when conditions exist as of the balance sheet date that indicate that the fair value of the investment may be less than book value. Eversource continually monitors and evaluates its equity method investments to determine if there are indicators of an other-than-temporary impairment. If the decline in value is considered to be other-than-temporary, the investment is written down to its estimated fair value, which establishes a new cost basis in the investment. Subsequent declines or recoveries after the reporting date are not considered in the impairment recognized. Investments that are other-than-temporarily impaired and written down to their estimated fair value cannot subsequently be written back up for increases in estimated fair value. Impairment evaluations involve a significant degree of judgment and estimation, including identifying circumstances that indicate an impairment may exist at the equity method investment level, selecting discount rates used to determine fair values, and developing an estimate of discounted future cash flows expected from investment operations or the sale of the investment. In the first quarter of 2024, there were no indicators of an other-than-temporary impairment in Eversource’s equity method investment balance. 2023 Liquidation of Renewable Energy Investment Fund: On March 21, 2023, Eversource’s equity method investment in a renewable energy investment fund was liquidated by the fund’s general partner in accordance with the partnership agreement. Proceeds received from the liquidation of $123.4 million were received in the first quarter of 2023 and were included in Investments in Unconsolidated Affiliates within investing activities on the statement of cash flows. A portion of the proceeds was used to make a charitable contribution to the Eversource Energy Foundation (a related party) of $20.0 million in the first quarter of 2023. The liquidation benefit received in excess of the investment’s carrying value and the charitable contribution are included in Other Income, Net on the statement of income. F. Other Taxes Eversource's companies that serve customers in Connecticut collect gross receipts taxes levied by the state of Connecticut from their customers. These gross receipts taxes are recorded separately with collections in Operating Revenues and with payments in Taxes Other Than Income Taxes on the statements of income as follows: For the Three Months Ended (Millions of Dollars) March 31, 2024 March 31, 2023 Eversource $ 53.3 $ 55.0 CL&P 43.9 43.1 As agents for state and local governments, Eversource's companies that serve customers in Connecticut and Massachusetts collect certain sales taxes that are recorded on a net basis with no impact on the statements of income. G. Supplemental Cash Flow Information Non-cash investing activities include plant additions included in Accounts Payable as follows: (Millions of Dollars) As of March 31, 2024 As of March 31, 2023 Eversource $ 453.6 $ 400.8 CL&P 112.8 101.9 NSTAR Electric 132.7 117.4 PSNH 75.2 54.6 The following table reconciles cash as reported on the balance sheets to the cash and restricted cash balance as reported on the statements of cash flows: As of March 31, 2024 As of December 31, 2023 (Millions of Dollars) Eversource CL&P NSTAR Electric PSNH Eversource CL&P NSTAR Electric PSNH Cash as reported on the Balance Sheets $ 259.2 $ 29.0 $ 20.2 $ 14.1 $ 53.9 $ 10.2 $ 6.7 $ 0.2 Restricted cash included in: Special Deposits 68.7 2.1 16.3 17.0 81.5 2.0 16.1 31.6 Marketable Securities 16.0 — — — 13.7 — — — Other Long-Term Assets 16.5 — — 3.2 17.3 — — 3.2 Cash and Restricted Cash as reported on the Statements of Cash Flows $ 360.4 $ 31.1 $ 36.5 $ 34.3 $ 166.4 $ 12.2 $ 22.8 $ 35.0 Special Deposits represent cash collections related to the PSNH RRB customer charges that are held in trust, required ISO-NE cash deposits, cash held in escrow accounts, and CYAPC and YAEC cash balances. Special Deposits are included in Current Assets on the balance sheets. As of both March 31, 2024 and December 31, 2023, restricted cash included in Marketable Securities represented money market funds held in restricted trusts to fund CYAPC and YAEC's spent nuclear fuel storage obligations. Eversource’s restricted cash includes an Energy Relief Fund for energy efficiency and clean energy measures in the Merrimack Valley established under the terms of the EGMA 2020 settlement agreement. This restricted cash held in escrow accounts included $20.0 million recorded as short-term in Special Deposits as of both March 31, 2024 and December 31, 2023, and $13.3 million and $14.1 million recorded in Other Long-Term Assets on the balance sheets as of March 31, 2024 and December 31, 2023, respectively.

REGULATORY ACCOUNTING

REGULATORY ACCOUNTING	3 Months Ended
REGULATORY ACCOUNTING	Mar. 31, 2024
Regulated Operations [Abstract]
REGULATORY ACCOUNTING	REGULATORY ACCOUNTING Eversource's utility companies are subject to rate regulation that is based on cost recovery and meets the criteria for application of accounting guidance for rate-regulated operations, which considers the effect of regulation on the timing of the recognition of certain revenues and expenses. The regulated companies' financial statements reflect the effects of the rate-making process. The rates charged to the customers of Eversource's regulated companies are designed to collect each company's costs to provide service, plus a return on investment. The application of accounting guidance for rate-regulated enterprises results in recording regulatory assets and liabilities. Regulatory assets represent the deferral of incurred costs that are probable of future recovery in customer rates. Regulatory assets are amortized as the incurred costs are recovered through customer rates. Regulatory liabilities represent either revenues received from customers to fund expected costs that have not yet been incurred or probable future refunds to customers. Management believes it is probable that each of the regulated companies will recover its respective investments in long-lived assets and the regulatory assets that have been recorded. If management were to determine that it could no longer apply the accounting guidance applicable to rate-regulated enterprises, or if management could not conclude it is probable that costs would be recovered from customers in future rates, the applicable costs would be charged to net income in the period in which the determination is made. Regulatory Assets: The components of regulatory assets were as follows: As of March 31, 2024 As of December 31, 2023 (Millions of Dollars) Eversource CL&P NSTAR PSNH Eversource CL&P NSTAR PSNH Storm Costs, Net $ 1,942.7 $ 957.6 $ 657.3 $ 327.8 $ 1,785.9 $ 896.6 $ 609.1 $ 280.2 Regulatory Tracking Mechanisms 1,541.2 593.5 522.3 184.9 1,319.2 354.5 482.9 182.2 Benefit Costs 1,098.1 194.5 330.2 78.0 1,117.3 197.4 336.7 79.3 Income Taxes, Net 925.7 517.5 133.6 15.5 912.4 512.6 128.6 16.4 Securitized Stranded Costs 381.7 — — 381.7 392.5 — — 392.5 Goodwill-related 259.9 — 223.1 — 264.1 — 226.7 — Asset Retirement Obligations 141.0 39.1 73.8 4.9 137.9 38.5 72.3 4.7 Derivative Liabilities 103.7 103.7 — — 120.9 120.9 — — Other Regulatory Assets 334.8 21.8 100.6 6.8 339.0 22.7 101.6 8.0 Total Regulatory Assets 6,728.8 2,427.7 2,040.9 999.6 6,389.2 2,143.2 1,957.9 963.3 Less: Current Portion 1,889.5 717.6 718.7 188.1 1,674.2 480.4 676.1 189.5 Total Long-Term Regulatory Assets $ 4,839.3 $ 1,710.1 $ 1,322.2 $ 811.5 $ 4,715.0 $ 1,662.8 $ 1,281.8 $ 773.8 Regulatory Costs in Other Long-Term Assets: Eversource's regulated companies had $243.9 million (including $169.2 million for CL&P, $21.7 million for NSTAR Electric and $1.3 million for PSNH) and $241.7 million (including $166.7 million for CL&P, $21.9 million for NSTAR Electric and $1.2 million for PSNH) of additional regulatory costs not yet specifically approved as of March 31, 2024 and December 31, 2023, respectively, that were included in Other Long-Term Assets on the balance sheets. These amounts will be reclassified to Regulatory Assets upon approval by the applicable regulatory agency. Based on regulatory policies or past precedent on similar costs, management believes it is probable that these costs will ultimately be approved and recovered from customers in rates. As of March 31, 2024 and December 31, 2023, these regulatory costs included $75.9 million (including $60.7 million for CL&P and $6.5 million for NSTAR Electric) and $82.1 million (including $64.0 million for CL&P and $7.3 million for NSTAR Electric), respectively, of deferred uncollectible hardship costs. Regulatory Liabilities: The components of regulatory liabilities were as follows: As of March 31, 2024 As of December 31, 2023 (Millions of Dollars) Eversource CL&P NSTAR PSNH Eversource CL&P NSTAR PSNH EDIT due to Tax Cuts and Jobs Act of 2017 $ 2,537.0 $ 966.1 $ 899.5 $ 337.5 $ 2,548.6 $ 969.2 $ 905.1 $ 339.3 Regulatory Tracking Mechanisms 711.7 167.5 384.2 80.2 668.3 154.0 347.2 114.4 Cost of Removal 687.6 168.2 431.0 14.8 666.6 157.9 420.9 16.2 Deferred Portion of Non-Service Income 373.2 53.1 184.9 38.2 354.0 49.9 175.9 36.6 AFUDC - Transmission 135.5 58.5 77.0 — 124.3 56.1 68.2 — Benefit Costs 44.8 0.5 18.0 — 51.0 0.6 22.2 — Other Regulatory Liabilities 203.1 37.3 13.7 4.8 201.9 30.4 13.9 4.6 Total Regulatory Liabilities 4,692.9 1,451.2 2,008.3 475.5 4,614.7 1,418.1 1,953.4 511.1 Less: Current Portion 641.5 117.3 405.2 86.1 591.8 102.2 368.1 117.5 Total Long-Term Regulatory Liabilities $ 4,051.4 $ 1,333.9 $ 1,603.1 $ 389.4 $ 4,022.9 $ 1,315.9 $ 1,585.3 $ 393.6

PROPERTY, PLANT AND EQUIPMENT A

PROPERTY, PLANT AND EQUIPMENT AND ACCUMULATED DEPRECIATION	3 Months Ended
PROPERTY, PLANT AND EQUIPMENT AND ACCUMULATED DEPRECIATION	Mar. 31, 2024
Property, Plant and Equipment [Abstract]
PROPERTY, PLANT AND EQUIPMENT AND ACCUMULATED DEPRECIATION	PROPERTY, PLANT AND EQUIPMENT AND ACCUMULATED DEPRECIATION The following tables summarize property, plant and equipment by asset category: Eversource As of March 31, 2024 As of December 31, 2023 (Millions of Dollars) Distribution - Electric $ 19,929.5 $ 19,656.5 Distribution - Natural Gas 8,234.7 8,155.3 Transmission - Electric 15,182.6 14,666.8 Distribution - Water 2,294.9 2,280.1 Solar 201.1 201.1 Utility 45,842.8 44,959.8 Other (1) 2,069.3 2,006.8 Property, Plant and Equipment, Gross 47,912.1 46,966.6 Less: Accumulated Depreciation Utility (9,835.7) (9,670.1) Other (916.2) (869.6) Total Accumulated Depreciation (10,751.9) (10,539.7) Property, Plant and Equipment, Net 37,160.2 36,426.9 Construction Work in Progress 3,129.2 3,071.7 Total Property, Plant and Equipment, Net $ 40,289.4 $ 39,498.6 As of March 31, 2024 As of December 31, 2023 (Millions of Dollars) CL&P NSTAR PSNH CL&P NSTAR PSNH Distribution - Electric $ 8,003.9 $ 9,138.5 $ 2,827.4 $ 7,897.1 $ 9,000.5 $ 2,799.2 Transmission - Electric 6,609.2 6,014.5 2,560.5 6,548.2 5,630.8 2,489.5 Solar — 201.1 — — 201.1 — Property, Plant and Equipment, Gross 14,613.1 15,354.1 5,387.9 14,445.3 14,832.4 5,288.7 Less: Accumulated Depreciation (2,707.9) (3,648.7) (1,004.7) (2,670.5) (3,585.9) (984.0) Property, Plant and Equipment, Net 11,905.2 11,705.4 4,383.2 11,774.8 11,246.5 4,304.7 Construction Work in Progress 627.3 1,334.9 324.4 565.4 1,507.3 270.0 Total Property, Plant and Equipment, Net $ 12,532.5 $ 13,040.3 $ 4,707.6 $ 12,340.2 $ 12,753.8 $ 4,574.7 (1) These assets are primarily comprised of computer software, hardware and equipment at Eversource Service and buildings at The Rocky River Realty Company.

DERIVATIVE INSTRUMENTS

DERIVATIVE INSTRUMENTS	3 Months Ended
DERIVATIVE INSTRUMENTS	Mar. 31, 2024
Derivative Instruments and Hedging Activities Disclosure [Abstract]
DERIVATIVE INSTRUMENTS	DERIVATIVE INSTRUMENTS The electric and natural gas companies purchase and procure energy and energy-related products, which are subject to price volatility, for their customers. The costs associated with supplying energy to customers are recoverable from customers in future rates. These regulated companies manage the risks associated with the price volatility of energy and energy-related products through the use of derivative and non-derivative contracts. Many of the derivative contracts meet the definition of, and are designated as, normal and qualify for accrual accounting under the applicable accounting guidance. The costs and benefits of derivative contracts that meet the definition of normal are recognized in Operating Expenses on the statements of income as electricity or natural gas is delivered. Derivative contracts that are not designated as normal are recorded at fair value as derivative assets or liabilities on the balance sheets. For the electric and natural gas companies, regulatory assets or regulatory liabilities are recorded to offset the fair values of derivatives, as contract settlement amounts are recovered from, or refunded to, customers in their respective energy supply rates. The gross fair values of derivative assets and liabilities with the same counterparty are offset and reported as net Derivative Assets or Derivative Liabilities, with current and long-term portions, on the balance sheets. The following table presents the gross fair values of contracts, categorized by risk type, and the net amounts recorded as current or long-term derivative assets or liabilities: As of March 31, 2024 As of December 31, 2023 CL&P (Millions of Dollars) Fair Value Hierarchy Commodity Supply and Price Risk Netting (1) Net Amount Commodity Supply and Price Risk Netting (1) Net Amount Current Derivative Assets Level 2 $ 15.8 $ (0.4) $ 15.4 $ 16.4 $ (0.5) $ 15.9 Long-Term Derivative Assets Level 2 9.9 (0.4) 9.5 13.6 (0.5) 13.1 Current Derivative Liabilities Level 2 (79.2) — (79.2) (81.9) — (81.9) Long-Term Derivative Liabilities Level 2 (49.4) — (49.4) (68.0) — (68.0) (1) Amounts represent derivative assets and liabilities that Eversource elected to record net on the balance sheets. These amounts are subject to master netting agreements or similar agreements for which the right of offset exists. Derivative Contracts at Fair Value with Offsetting Regulatory Amounts Commodity Supply and Price Risk Management : As required by regulation, CL&P, along with UI, has capacity-related contracts with generation facilities. CL&P has a sharing agreement with UI, with 80 percent of the costs or benefits of each contract borne by or allocated to CL&P and 20 percent borne by or allocated to UI. The combined capacities of these contracts as of both March 31, 2024 and December 31, 2023 were 682 MW. The capacity contracts extend through 2026 and obligate both CL&P and UI to make or receive payments on a monthly basis to or from the generation facilities based on the difference between a set capacity price and the capacity market price received in the ISO-NE capacity markets. For the three months ended March 31, 2024 and 2023, there were losses of $1.0 million and $1.9 million, respectively, deferred as regulatory costs, which reflect the change in fair value associated with CL&P’s derivative contracts. Fair Value Measurements of Derivative Instruments The fair value of derivative contracts utilizes both observable and unobservable inputs. The fair value is modeled using income techniques, such as discounted cash flow valuations adjusted for assumptions related to exit price. Valuations of derivative contracts using a discounted cash flow methodology include assumptions regarding the timing and likelihood of scheduled capacity payments and also reflect non-performance risk, including credit, using the default probability approach based on the counterparty's credit rating for assets and the Company's credit rating for liabilities. Significant observable inputs for valuations of these contracts include energy-related product prices in future years for which quoted prices in an active market exist. Valuations incorporate estimates of premiums or discounts that would be required by a market participant to arrive at an exit price, using historical market transactions adjusted for the terms of the contract. Fair value measurements were prepared by individuals with expertise in valuation techniques, pricing of energy-related products, and accounting requirements. All derivative contracts were classified as Level 2 in the fair value hierarchy as of both March 31, 2024 and December 31, 2023. The following table presents changes in the Level 3 category of derivative assets and derivative liabilities measured at fair value on a recurring basis. The derivative assets and liabilities are presented on a net basis. CL&P For the Three Months Ended March 31, 2023 (Millions of Dollars) Derivatives, Net: Fair Value as of Beginning of Period $ (181.8) Net Realized/Unrealized Losses Included in Regulatory Assets (1.9) Settlements 14.9 Fair Value as of End of Period $ (168.8)

MARKETABLE SECURITIES

MARKETABLE SECURITIES	3 Months Ended
MARKETABLE SECURITIES	Mar. 31, 2024
Investments, Debt and Equity Securities [Abstract]
MARKETABLE SECURITIES	MARKETABLE SECURITIES Eversource’s marketable securities include the CYAPC and YAEC legally restricted trusts that each hold equity and available-for-sale debt securities to fund the spent nuclear fuel removal obligations of their nuclear fuel storage facilities. Eversource also holds trusts that are not subject to regulatory oversight by state or federal agencies that are primarily used to fund certain non-qualified executive benefits. The marketable securities within the non-qualified executive benefit trusts were sold in 2023. Equity and available-for-sale debt marketable securities are recorded at fair value, with the current portion recorded in Prepayments and Other Current Assets and the long-term portion recorded in Marketable Securities on the balance sheets. Equity Securities: Eversource's equity securities include CYAPC's and YAEC's marketable securities held in spent nuclear fuel trusts, which had fair values of $172.3 million and $173.6 million as of March 31, 2024 and December 31, 2023, respectively. Unrealized gains and losses for these spent nuclear fuel trusts are subject to regulatory accounting treatment and are recorded in long-term Marketable Securities with the corresponding offset to long-term liabilities on the balance sheets, with no impact on the statements of income. Unrealized gains and losses on equity securities held in Eversource's trusts are recorded in Other Income, Net on the statements of income. The equity securities within Eversource’s non-qualified executive benefits trusts were sold during 2023. The fair value of equity securities held in Eversource’s trusts as of March 31, 2024 and December 31, 2023 were $3.7 million and $3.3 million, respectively. For the three months ended March 31, 2024 and 2023, there were unrealized gains of $0.4 million and $0.8 million recorded in Other Income, Net related to these equity securities. Available-for-Sale Debt Securities: The following is a summary of the available-for-sale debt securities: As of March 31, 2024 As of December 31, 2023 Eversource (Millions of Dollars) Amortized Cost Pre-Tax Pre-Tax Fair Value Amortized Cost Pre-Tax Pre-Tax Fair Value Debt Securities $ 170.5 $ 0.2 $ (8.7) $ 162.0 $ 169.5 $ 1.4 $ (6.6) $ 164.3 Eversource's debt securities include CYAPC's and YAEC's marketable securities held in spent nuclear fuel trusts in the amounts of $162.0 million and $164.3 million as of March 31, 2024 and December 31, 2023, respectively. Unrealized gains and losses for available-for-sale debt securities included in the CYAPC and YAEC spent nuclear fuel trusts are subject to regulatory accounting treatment and are recorded in Marketable Securities with the corresponding offset to long-term liabilities on the balance sheets, with no impact on the statements of income. CYAPC and YAEC’s spent nuclear fuel trusts are restricted and are classified in long-term Marketable Securities on the balance sheets. The debt securities within Eversource’s non-qualified executive benefits trusts were sold during 2023. Any unrealized gains and losses on available-for-sale debt securities held in Eversource's trusts are recorded in Accumulated Other Comprehensive Income, excluding amounts related to credit losses or losses on securities intended to be sold, which are recorded in Other Income, Net. There were no credit losses for the three months ended March 31, 2024 and 2023, and no allowance for credit losses as of March 31, 2024. Factors considered in determining whether a credit loss exists include adverse conditions specifically affecting the issuer, the payment history, ratings and rating changes of the security, and the severity of the impairment. For asset-backed debt securities, underlying collateral and expected future cash flows are also evaluated. As of March 31, 2024, the contractual maturities of available-for-sale debt securities were as follows: Eversource (Millions of Dollars) Amortized Cost Fair Value Less than one year $ 19.4 $ 19.4 One to five years 31.5 31.0 Six to ten years 37.7 36.4 Greater than ten years 81.9 75.2 Total Debt Securities $ 170.5 $ 162.0 Realized Gains and Losses: Realized gains and losses are recorded in Other Income, Net for Eversource's benefit trusts and are offset in long-term liabilities for CYAPC and YAEC. Eversource utilizes the specific identification basis method for the Eversource non-qualified benefit trusts, and the average cost basis method for the CYAPC and YAEC spent nuclear fuel trusts to compute the realized gains and losses on the sale of marketable securities. Fair Value Measurements: The following table presents the marketable securities recorded at fair value on a recurring basis by the level in which they are classified within the fair value hierarchy: Eversource (Millions of Dollars) As of March 31, 2024 As of December 31, 2023 Level 1: Mutual Funds and Equities $ 176.0 $ 176.9 Money Market Funds 16.0 13.7 Total Level 1 $ 192.0 $ 190.6 Level 2: U.S. Government Issued Debt Securities (Agency and Treasury) $ 89.2 $ 90.1 Corporate Debt Securities 34.2 34.0 Asset-Backed Debt Securities 5.4 5.6 Municipal Bonds 7.3 9.8 Other Fixed Income Securities 9.9 11.1 Total Level 2 $ 146.0 $ 150.6 Total Marketable Securities $ 338.0 $ 341.2 U.S. government issued debt securities are valued using market approaches that incorporate transactions for the same or similar bonds and adjustments for yields and maturity dates. Corporate debt securities are valued using a market approach, utilizing recent trades of the same or similar instruments and also incorporating yield curves, credit spreads and specific bond terms and conditions. Asset-backed debt securities include collateralized mortgage obligations, commercial mortgage backed securities, and securities collateralized by auto loans, credit card loans or receivables. Asset-backed debt securities are valued using recent trades of similar instruments, prepayment assumptions, yield curves, issuance and maturity dates, and tranche information. Municipal bonds are valued using a market approach that incorporates reported trades and benchmark yields. Other fixed income securities are valued using pricing models, quoted prices of securities with similar characteristics, and discounted cash flows.

SHORT-TERM AND LONG-TERM DEBT

SHORT-TERM AND LONG-TERM DEBT	3 Months Ended
SHORT-TERM AND LONG-TERM DEBT	Mar. 31, 2024
Debt Disclosure [Abstract]
SHORT-TERM AND LONG-TERM DEBT	SHORT-TERM AND LONG-TERM DEBT Short-Term Debt - Commercial Paper Programs and Credit Agreements : Eversource parent has a $2.00 billion commercial paper program allowing Eversource parent to issue commercial paper as a form of short-term debt. Eversource parent, CL&P, PSNH, NSTAR Gas, Yankee Gas, EGMA and Aquarion Water Company of Connecticut are parties to a five-year $2.00 billion revolving credit facility, which terminates on October 13, 2028. This revolving credit facility serves to backstop Eversource parent's $2.00 billion commercial paper program. NSTAR Electric has a $650 million commercial paper program allowing NSTAR Electric to issue commercial paper as a form of short-term debt. NSTAR Electric is also a party to a five-year $650 million revolving credit facility, which terminates on October 13, 2028, that serves to backstop NSTAR Electric's $650 million commercial paper program. The amount of borrowings outstanding and available under the commercial paper programs were as follows: Borrowings Outstanding as of Available Borrowing Capacity as of Weighted-Average Interest Rate as of March 31, 2024 December 31, 2023 March 31, 2024 December 31, 2023 March 31, 2024 December 31, 2023 (Millions of Dollars) Eversource Parent Commercial Paper Program $ 1,934.9 $ 1,771.9 $ 65.1 $ 228.1 5.66 % 5.60 % NSTAR Electric Commercial Paper Program 419.0 365.8 231.0 284.2 5.38 % 5.40 % There were no borrowings outstanding on the revolving credit facilities as of March 31, 2024 or December 31, 2023. CL&P and PSNH have uncommitted line of credit agreements totaling $375 million and $250 million, respectively, which will expire in 2024. There are no borrowings outstanding on either the CL&P or PSNH uncommitted line of credit agreements as of March 31, 2024. Amounts outstanding under the commercial paper programs are included in Notes Payable and classified in current liabilities on the Eversource and NSTAR Electric balance sheets, as all borrowings are outstanding for no more than 364 days at one time. As a result of the CL&P long-term debt issuance in January 2024, $207.3 million of commercial paper borrowings under the Eversource parent commercial paper program were reclassified to Long-Term Debt on Eversource parent’s balance sheet as of December 31, 2023. As a result of the PSNH long-term debt issuance in April 2024, $251.0 million of commercial paper borrowings under the Eversource parent commercial paper program were reclassified to Long-Term Debt on Eversource parent’s balance sheet as of March 31, 2024. Intercompany Borrowings: Eversource parent uses its available capital resources to provide loans to its subsidiaries to assist in meeting their short-term borrowing needs. Eversource parent records intercompany interest income from its loans to subsidiaries, which is eliminated in consolidation. Intercompany loans from Eversource parent to its subsidiaries are eliminated in consolidation on Eversource's balance sheets. As of March 31, 2024, there were intercompany loans from Eversource parent to CL&P of $426.1 million and to PSNH of $251.0 million. As of December 31, 2023, there were intercompany loans from Eversource parent to CL&P of $457.0 million and to PSNH of $233.0 million. Eversource parent charges interest on these intercompany loans at the same weighted-average interest rate as its commercial paper program. Intercompany loans from Eversource parent are included in Notes Payable to Eversource Parent and classified in current liabilities on the respective subsidiary's balance sheets, as these intercompany borrowings are outstanding for no more than 364 days at one time. As a result of the CL&P long-term debt issuance in January 2024, $207.3 million of CL&P’s intercompany borrowings were reclassified to Long-Term Debt on CL&P’s balance sheet as of December 31, 2023. As a result of the PSNH long-term debt issuance in April 2024, $251.0 million of PSNH’s intercompany borrowings were reclassified to Long-Term Debt on PSNH’s balance sheet as of March 31, 2024. Sources and Uses of Cash: The Company expects the future operating cash flows of Eversource, CL&P, NSTAR Electric and PSNH, along with existing borrowing availability and access to both debt and equity markets, will be sufficient to meet any working capital and future operating requirements, and capital investment forecasted opportunities. Long-Term Debt Issuance Authorizations: On February 8, 2024, the NHPUC approved PSNH’s request for authorization to issue up to $300 million in long-term debt through December 31, 2024. On May 1, 2024, the DPU approved NSTAR Electric’s request for authorization to issue up to $2.4 billion in long-term debt through December 31, 2026. Long-Term Debt Issuances and Repayments: The following table summarizes long-term debt issuances and repayments: (Millions of Dollars) Interest Rate Issuance/(Repayment) Issue Date or Repayment Date Maturity Date Use of Proceeds for Issuance/ CL&P 2024 Series A First Mortgage Bonds 4.65 % $ 350.0 January 2024 January 2029 Repaid short-term debt, paid capital expenditures and working capital PSNH Series X First Mortgage Bonds 5.35 % 300.0 April 2024 October 2033 Repaid short-term debt, paid capital expenditures and working capital Eversource Parent Series DD Senior Notes 5.00 % 350.0 January 2024 January 2027 Repaid short-term debt Eversource Parent Series EE Senior Notes 5.50 % 650.0 January 2024 January 2034 Repaid short-term debt Eversource Parent Series FF Senior Notes 5.85 % 700.0 April 2024 April 2031 Repay Series X Senior Notes and Aquarion’s 2014 Senior Notes at maturity and short-term debt Eversource Parent Series GG Senior Notes 5.95 % 700.0 April 2024 July 2034 Repay Series X Senior Notes and Aquarion’s 2014 Senior Notes at maturity and short-term debt As a result of the Eversource parent long-term debt issuances in April 2024, $1.39 billion of current portion of long-term debt was reclassified to Long-Term Debt on Eversource parent’s balance sheet as of March 31, 2024.

RATE REDUCTION BONDS AND VARIAB

RATE REDUCTION BONDS AND VARIABLE INTEREST ENTITIES	3 Months Ended
RATE REDUCTION BONDS AND VARIABLE INTEREST ENTITIES	Mar. 31, 2024
Rate Reduction Bonds and Variable Interest Entity [Abstract]
RATE REDUCTION BONDS AND VARIABLE INTEREST ENTITIES	RATE REDUCTION BONDS AND VARIABLE INTEREST ENTITIES Rate Reduction Bonds: In May 2018, PSNH Funding, a wholly-owned subsidiary of PSNH, issued $635.7 million of securitized RRBs in multiple tranches with a weighted average interest rate of 3.66 percent, and final maturity dates ranging from 2026 to 2035. The RRBs are expected to be repaid by February 1, 2033. RRB payments consist of principal and interest and are paid semi-annually, beginning on February 1, 2019. The RRBs were issued pursuant to a finance order issued by the NHPUC in January 2018 to recover remaining costs resulting from the divestiture of PSNH’s generation assets. PSNH Funding was formed solely to issue RRBs to finance PSNH's unrecovered remaining costs associated with the divestiture of its generation assets. PSNH Funding is considered a VIE primarily because the equity capitalization is insufficient to support its operations. PSNH has the power to direct the significant activities of the VIE and is most closely associated with the VIE as compared to other interest holders. Therefore, PSNH is considered the primary beneficiary and consolidates PSNH Funding in its consolidated financial statements. The following tables summarize the impact of PSNH Funding on PSNH's balance sheets and income statements: (Millions of Dollars) PSNH Balance Sheets: As of March 31, 2024 As of December 31, 2023 Restricted Cash - Current Portion (included in Special Deposits) $ 15.5 $ 30.0 Restricted Cash - Long-Term Portion (included in Other Long-Term Assets) 3.2 3.2 Securitized Stranded Cost (included in Regulatory Assets) 381.7 392.5 Other Regulatory Liabilities (included in Regulatory Liabilities) 5.7 5.3 Accrued Interest (included in Other Current Liabilities) 2.4 6.3 Rate Reduction Bonds - Current Portion 43.2 43.2 Rate Reduction Bonds - Long-Term Portion 345.7 367.3 (Millions of Dollars) PSNH Income Statements: For the Three Months Ended March 31, 2024 March 31, 2023 Amortization of RRB Principal (included in Amortization of Regulatory Assets/(Liabilities), Net) $ 10.8 $ 10.8 Interest Expense on RRB Principal (included in Interest Expense) 3.7 4.1

PENSION BENEFITS AND POSTRETIRE

PENSION BENEFITS AND POSTRETIREMENT BENEFITS OTHER THAN PENSION	3 Months Ended
	Mar. 31, 2024
Postemployment Benefits [Abstract]
PENSION BENEFITS AND POSTRETIREMENT BENEFITS OTHER THAN PENSION	PENSION BENEFITS AND POSTRETIREMENT BENEFITS OTHER THAN PENSION Eversource provides defined benefit retirement plans (Pension Plans) that cover eligible employees. In addition to the Pension Plans, Eversource maintains non-qualified defined benefit retirement plans (SERP Plans), which provide benefits in excess of Internal Revenue Code limitations to eligible participants consisting of current and retired employees. Eversource also provides defined benefit postretirement plans (PBOP Plans) that provide life insurance and a health reimbursement arrangement created for the purpose of reimbursing retirees and dependents for health insurance premiums and certain medical expenses to eligible employees that meet certain age and service eligibility requirements. The components of net periodic benefit plan expense/(income) for the Pension, SERP and PBOP Plans, prior to amounts capitalized as Property, Plant and Equipment or deferred as regulatory assets/(liabilities) for future recovery or refund, are shown below. The service cost component of net periodic benefit plan expense/(income), less the capitalized portion, is included in Operations and Maintenance expense on the statements of income. The remaining components of net periodic benefit plan expense/(income), less the deferred portion, are included in Other Income, Net on the statements of income. Pension, SERP and PBOP expense reflected in the statements of cash flows for CL&P, NSTAR Electric and PSNH does not include intercompany allocations of net periodic benefit plan expense/(income), as these amounts are cash settled on a short-term basis. Pension and SERP PBOP For the Three Months Ended March 31, 2024 For the Three Months Ended March 31, 2024 (Millions of Dollars) Eversource CL&P NSTAR PSNH Eversource CL&P NSTAR PSNH Service Cost $ 10.8 $ 2.9 $ 2.1 $ 1.0 $ 1.7 $ 0.3 $ 0.3 $ 0.1 Interest Cost 62.0 12.4 13.1 6.7 8.0 1.4 2.2 0.9 Expected Return on Plan Assets (115.6) (23.3) (28.3) (12.2) (20.4) (2.4) (9.9) (1.4) Actuarial Loss/(Gain) 19.8 2.5 6.4 1.1 (0.1) — — — Prior Service Cost/(Credit) 0.3 — 0.1 — (5.4) 0.3 (4.2) 0.1 Settlement Loss 4.3 — — — — — — — Total Net Periodic Benefit Plan Income $ (18.4) $ (5.5) $ (6.6) $ (3.4) $ (16.2) $ (0.4) $ (11.6) $ (0.3) Intercompany Expense/(Income) Allocations N/A $ 0.3 $ 0.4 $ 0.1 N/A $ (0.6) $ (0.7) $ (0.2) Pension and SERP PBOP For the Three Months Ended March 31, 2023 For the Three Months Ended March 31, 2023 (Millions of Dollars) Eversource CL&P NSTAR PSNH Eversource CL&P NSTAR PSNH Service Cost $ 11.0 $ 3.0 $ 2.1 $ 1.1 $ 1.8 $ 0.3 $ 0.3 $ 0.2 Interest Cost 63.7 12.6 13.5 6.8 8.5 1.6 2.3 0.9 Expected Return on Plan Assets (115.9) (23.4) (28.4) (12.3) (19.1) (2.4) (9.2) (1.4) Actuarial Loss 12.5 0.8 4.9 0.4 — — — — Prior Service Cost/(Credit) 0.3 — 0.1 — (5.4) 0.3 (4.2) 0.1 Total Net Periodic Benefit Plan Income $ (28.4) $ (7.0) $ (7.8) $ (4.0) $ (14.2) $ (0.2) $ (10.8) $ (0.2) Intercompany Income Allocations N/A $ (2.0) $ (1.7) $ (0.5) N/A $ (0.5) $ (0.6) $ (0.2)

COMMITMENTS AND CONTINGENCIES

COMMITMENTS AND CONTINGENCIES	3 Months Ended
COMMITMENTS AND CONTINGENCIES	Mar. 31, 2024
Commitments and Contingencies Disclosure [Abstract]
COMMITMENTS AND CONTINGENCIES	COMMITMENTS AND CONTINGENCIES A. Environmental Matters Eversource, CL&P, NSTAR Electric and PSNH are subject to environmental laws and regulations intended to mitigate or remove the effect of past operations and improve or maintain the quality of the environment. These laws and regulations require the removal or the remedy of the effect on the environment of the disposal or release of certain specified hazardous substances at current and former operating sites. Eversource, CL&P, NSTAR Electric and PSNH have an active environmental auditing and training program and each believes it is substantially in compliance with all enacted laws and regulations. The number of environmental sites and related reserves for which remediation or long-term monitoring, preliminary site work or site assessment is being performed are as follows: As of March 31, 2024 As of December 31, 2023 Number of Sites Reserve Number of Sites Reserve Eversource 66 $ 128.0 65 $ 128.2 CL&P 16 13.8 16 13.8 NSTAR Electric 13 5.9 12 5.4 PSNH 8 7.7 8 7.6 Included in the number of sites and reserve amounts above are former MGP sites that were operated several decades ago and manufactured natural gas from coal and other processes, which resulted in certain by-products remaining in the environment that may pose a potential risk to human health and the environment, for which Eversource may have potential liability. Eversource’s reserve balances related to these former MGP sites were $116.1 million and $117.1 million as of March 31, 2024 and December 31, 2023, respectively, and related primarily to the natural gas business segment. These reserve estimates are subjective in nature as they take into consideration several different remediation options at each specific site. The reliability and precision of these estimates can be affected by several factors, including new information concerning either the level of contamination at the site, the extent of Eversource's, CL&P's, NSTAR Electric's and PSNH's responsibility for remediation or the extent of remediation required, recently enacted laws and regulations or changes in cost estimates due to certain economic factors. It is possible that new information or future developments could require a reassessment of the potential exposure to required environmental remediation. As this information becomes available, management will continue to assess the potential exposure and adjust the reserves accordingly. B. Long-Term Contractual Arrangements PSNH’s estimated future annual costs of long-term renewable energy purchase contracts related to the purchase of capacity, energy and RECs from a New Hampshire generation plant and totaled $503.2 million as of December 31, 2023. The NHPUC approved the termination of the PPA related to this generation plant effective February 29, 2024. As of March 31, 2024, there are no remaining long-term renewable energy purchase contracts at PSNH. C. Guarantees and Indemnifications In the normal course of business, Eversource parent provides credit assurances on behalf of its subsidiaries, including CL&P, NSTAR Electric and PSNH, in the form of guarantees. Management does not anticipate a material impact to net income or cash flows as a result of these various guarantees and indemnifications. Guarantees issued on behalf of unconsolidated entities, including equity method offshore wind investments, for which Eversource parent is the guarantor, are recorded at fair value as a liability on the balance sheet at the inception of the guarantee. The fair value of guarantees issued on behalf of unconsolidated entities are recorded within Other Long-Term Liabilities on the balance sheet, and were $2.6 million and $4.4 million as of March 31, 2024 and December 31, 2023, respectively. Eversource regularly reviews performance risk under these guarantee arrangements, and believes the likelihood of payments being required under the guarantees is remote. In the event it becomes probable that Eversource parent will be required to perform under the guarantee, the amount of probable payment will be recorded. The following table summarizes Eversource parent's exposure to guarantees and indemnifications of its subsidiaries and affiliates to external parties, and primarily relates to its offshore wind business: As of March 31, 2024 Company (Obligor) Description Maximum Exposure North East Offshore, LLC, Sunrise Wind LLC, Revolution Wind, LLC and South Fork Wind, LLC Offshore wind construction-related purchase agreements with third-party contractors (1) $ 1,824.3 Eversource Investment LLC and South Fork Class B Member, LLC Funding and indemnification obligations of South Fork Wind and North East Offshore, LLC (2) 458.5 Sunrise Wind LLC OREC capacity production (3) 15.4 South Fork Wind, LLC Power Purchase Agreement Security (4) 7.1 Eversource Investment LLC Letters of Credit (5) 23.2 Eversource TEI LLC South Fork Wind Tax Equity (6) 50.0 Various Eversource subsidiaries Surety bonds (7) 38.8 Sunrise Wind LLC Surety bonds (8) 48.2 (1) Eversource parent issued guarantees on behalf of its 50 percent-owned affiliates, North East Offshore, LLC (NEO), Sunrise Wind LLC, Revolution Wind, LLC and South Fork Wind, LLC, under which Eversource parent agreed to guarantee each entity’s performance of obligations under certain construction-related purchase agreements with third-party contractors, in an aggregate amount not to exceed $3.02 billion. Eversource parent’s obligations under the guarantees expire upon the earlier of (i) dates ranging between May 2024 and October 2028 and (ii) full performance of the guaranteed obligations. Eversource parent also issued a separate guarantee to Ørsted on behalf of NEO, under which Eversource parent agreed to guarantee 50 percent of NEO’s payment obligations under certain offshore wind project construction-related agreements with Ørsted in an aggregate amount not to exceed $62.5 million and expiring upon full performance of the guaranteed obligation. (2) Eversource parent issued guarantees on behalf of its wholly-owned subsidiary Eversource Investment LLC (EI), which holds Eversource's investments in offshore wind-related equity method investments, and on behalf of its 50 percent-owned affiliate, South Fork Class B Member, LLC, whereby Eversource parent will guarantee each entity’s performance of certain capital expenditure funding obligations during the construction phases of the South Fork Wind project and NEO’s underlying offshore wind projects. Eversource parent also guaranteed certain indemnification obligations of EI associated with third party credit support for EI’s investment in NEO. These guarantees will not exceed $1.52 billion and expire upon the full performance of the guaranteed obligations. (3) Eversource parent issued a guarantee on behalf of its 50 percent-owned affiliate, Sunrise Wind LLC, whereby Eversource parent will guarantee Sunrise Wind LLC's performance of certain obligations, in an amount not to exceed $15.4 million, under the Offshore Wind Renewable Energy Certificate Purchase and Sale Agreement (the Agreement). The Agreement was executed by and between the New York State Energy Research and Development Authority (NYSERDA) and Sunrise Wind LLC. The guarantee expires upon the full performance of the guaranteed obligations. (4) Eversource parent issued a guarantee on behalf of its 50 percent-owned affiliate, South Fork Wind, LLC, whereby Eversource parent will guarantee South Fork Wind, LLC's performance of certain obligations, in an amount not to exceed $7.1 million, under a Power Purchase Agreement between the Long Island Power Authority and South Fork Wind, LLC (the Agreement). The guarantee expires upon the later of (i) the end of the Agreement term and (ii) full performance of the guaranteed obligations. (5) Eversource parent entered into a guarantee on behalf of EI, under which Eversource parent would guarantee EI's obligations under a letter of credit facility with a financial institution that EI may request in an aggregate amount of up to approximately $25 million. As of March 31, 2024, EI has issued letters of credit on behalf of South Fork Wind, LLC, Sunrise Wind LLC and Revolution Wind, LLC totaling $23.2 million. The guarantee will remain in effect until full performance of the guaranteed obligations. (6) Eversource parent issued a guarantee on behalf of its wholly-owned subsidiary, Eversource TEI LLC, whereby Eversource parent will guarantee Eversource TEI LLC’s performance of certain obligations, in an amount not to exceed $50.0 million, in connection with any remaining obligations under the LLC agreement. Eversource parent’s obligations expire upon the full performance of the guaranteed obligations. (7) Surety bonds expire in 2024 and 2025. Expiration dates reflect termination dates, the majority of which will be renewed or extended. Certain surety bonds contain credit ratings triggers that would require Eversource parent to post collateral in the event that the unsecured debt credit ratings of Eversource parent are downgraded. (8) Sunrise Wind LLC issued surety bonds related to future remediation obligations of certain onshore transmission assets totaling $48.2 million. One surety bond expires in March 2025 and the other surety bonds will remain outstanding until full performance of the related obligations. D. Spent Nuclear Fuel Obligations - Yankee Companies CL&P, NSTAR Electric and PSNH have plant closure and fuel storage cost obligations to the Yankee Companies, which have each completed the physical decommissioning of their respective nuclear power facilities and are now engaged in the long-term storage of their spent fuel. The Yankee Companies fund these costs through litigation proceeds received from the DOE and, to the extent necessary, through wholesale, FERC-approved rates charged under power purchase agreements with several New England utilities, including CL&P, NSTAR Electric and PSNH. CL&P, NSTAR Electric and PSNH, in turn recover these costs from their customers through state regulatory commission-approved retail rates. The Yankee Companies collect amounts that management believes are adequate to recover the remaining plant closure and fuel storage cost estimates for the respective plants. Management believes CL&P and NSTAR Electric will recover their shares of these obligations from their customers. PSNH has recovered its total share of these costs from its customers. Spent Nuclear Fuel Litigation: The Yankee Companies have filed complaints against the DOE in the Court of Federal Claims seeking monetary damages resulting from the DOE's failure to accept delivery of, and provide for a permanent facility to store, spent nuclear fuel pursuant to the terms of the 1983 spent fuel and high-level waste disposal contracts between the Yankee Companies and the DOE. The court previously awarded the Yankee Companies damages for Phases I, II, III and IV of litigation resulting from the DOE's failure to meet its contractual obligations. These Phases covered damages incurred in the years 1998 through 2016, and the awarded damages have been received by the Yankee Companies with certain amounts of the damages refunded to their customers. DOE Phase V Damages - On March 25, 2021, each of the Yankee Companies filed a fifth set of lawsuits against the DOE in the Court of Federal Claims resulting from the DOE's failure to begin accepting spent nuclear fuel for disposal covering the years from 2017 to 2020. The Yankee Companies filed claims seeking monetary damages totaling $120.4 million for CYAPC, YAEC and MYAPC. Pursuant to a June 2, 2022 court order, the Yankee Companies were subsequently permitted to include monetary damages relating to the year 2021 in the DOE Phase V complaint. The Yankee Companies submitted a supplemental filing to include these costs of $33.1 million on June 8, 2022. On March 13, 2024, the court issued an order establishing a schedule to resolve pending discovery issues by June 10, 2024, after which the court will set dates for further proceedings in the DOE Phase V trial. E. FERC ROE Complaints Four separate complaints were filed at the FERC by combinations of New England state attorneys general, state regulatory commissions, consumer advocates, consumer groups, municipal parties and other parties (collectively, the Complainants). In each of the first three complaints, filed on October 1, 2011, December 27, 2012, and July 31, 2014, respectively, the Complainants challenged the NETOs' base ROE of 11.14 percent that had been utilized since 2005 and sought an order to reduce it prospectively from the date of the final FERC order and for the separate 15-month complaint periods. In the fourth complaint, filed April 29, 2016, the Complainants challenged the NETOs' base ROE billed of 10.57 percent and the maximum ROE for transmission incentive (incentive cap) of 11.74 percent, asserting that these ROEs were unjust and unreasonable. The ROE originally billed during the period October 1, 2011 (beginning of the first complaint period) through October 15, 2014 consisted of a base ROE of 11.14 percent and incentives up to 13.1 percent. On October 16, 2014, FERC issued Opinion No. 531-A and set the base ROE at 10.57 percent and the incentive cap at 11.74 percent for the first complaint period. This was also effective for all prospective billings to customers beginning October 16, 2014. This FERC order was vacated on April 14, 2017 by the U.S. Court of Appeals for the D.C. Circuit (the Court). All amounts associated with the first complaint period have been refunded, which totaled $38.9 million (pre-tax and excluding interest) at Eversource and reflected both the base ROE and incentive cap prescribed by the FERC order. The refund consisted of $22.4 million for CL&P, $13.7 million for NSTAR Electric and $2.8 million for PSNH. Eversource has recorded a reserve of $39.1 million (pre-tax and excluding interest) for the second complaint period as of both March 31, 2024 and December 31, 2023. This reserve represents the difference between the billed rates during the second complaint period and a 10.57 percent base ROE and 11.74 percent incentive cap. The reserve consisted of $21.4 million for CL&P, $14.6 million for NSTAR Electric and $3.1 million for PSNH as of both March 31, 2024 and December 31, 2023. On October 16, 2018, FERC issued an order on all four complaints describing how it intends to address the issues that were remanded by the Court. FERC proposed a new framework to determine (1) whether an existing ROE is unjust and unreasonable and, if so, (2) how to calculate a replacement ROE. Initial briefs were filed by the NETOs, Complainants and FERC Trial Staff on January 11, 2019 and reply briefs were filed on March 8, 2019. The NETOs' brief was supportive of the overall ROE methodology determined in the October 16, 2018 order provided the FERC does not change the proposed methodology or alter its implementation in a manner that has a material impact on the results. The FERC order included illustrative calculations for the first complaint using FERC's proposed frameworks with financial data from that complaint. Those illustrative calculations indicated that for the first complaint period, for the NETOs, which FERC concludes are of average financial risk, the preliminary just and reasonable base ROE is 10.41 percent and the preliminary incentive cap on total ROE is 13.08 percent. If the results of the illustrative calculations were included in a final FERC order for each of the complaint periods, then a 10.41 percent base ROE and a 13.08 percent incentive cap would not have a significant impact on our financial statements for all of the complaint periods. These preliminary calculations are not binding and do not represent what we believe to be the most likely outcome of a final FERC order. On November 21, 2019, FERC issued Opinion No. 569 affecting the two pending transmission ROE complaints against the Midcontinent ISO (MISO) transmission owners, in which FERC adopted a new methodology for determining base ROEs. Various parties sought rehearing. On December 23, 2019, the NETOs filed supplementary materials in the NETOs' four pending cases to respond to this new methodology because of the uncertainty of the applicability to the NETOs' cases. On May 21, 2020, the FERC issued its order in Opinion No. 569-A on the rehearing of the MISO transmission owners' cases, in which FERC again changed its methodology for determining the MISO transmission owners' base ROEs. On November 19, 2020, the FERC issued Opinion No. 569-B denying rehearing of Opinion No. 569-A and reaffirmed the methodology previously adopted in Opinion No. 569-A. The new methodology differs significantly from the methodology proposed by FERC in its October 16, 2018 order to determine the NETOs' base ROEs in its four pending cases. FERC Opinion Nos. 569-A and 569-B were appealed to the Court. On August 9, 2022, the Court issued its decision vacating MISO ROE FERC Opinion Nos. 569, 569-A and 569-B and remanded to FERC to reopen the proceedings. The Court found that FERC’s development of the new return methodology was arbitrary and capricious due to FERC’s failure to offer a reasonable explanation for its decision to reintroduce the risk-premium financial model in its new methodology for calculating a just and reasonable return. At this time, Eversource cannot predict how and when FERC will address the Court’s findings on the remand of the MISO FERC opinions or any potential associated impact on the NETOs’ four pending ROE complaint cases. Given the significant uncertainty regarding the applicability of the FERC opinions in the MISO transmission owners’ two complaint cases to the NETOs’ pending four complaint cases, Eversource concluded that there is no reasonable basis for a change to the reserve or recognized ROEs for any of the complaint periods at this time. As well, Eversource cannot reasonably estimate a range of loss for any of the four complaint proceedings at this time. Eversource, CL&P, NSTAR Electric and PSNH currently record revenues at the 10.57 percent base ROE and incentive cap at 11.74 percent established in the October 16, 2014 FERC order.

FAIR VALUE OF FINANCIAL INSTRUM

FAIR VALUE OF FINANCIAL INSTRUMENTS	3 Months Ended
FAIR VALUE OF FINANCIAL INSTRUMENTS	Mar. 31, 2024
Fair Value Disclosures [Abstract]
FAIR VALUE OF FINANCIAL INSTRUMENTS	FAIR VALUE OF FINANCIAL INSTRUMENTS The following methods and assumptions were used to estimate the fair value of each of the following financial instruments: Preferred Stock, Long-Term Debt and Rate Reduction Bonds: The fair value of CL&P's and NSTAR Electric's preferred stock is based upon pricing models that incorporate interest rates and other market factors, valuations or trades of similar securities and cash flow projections. The fair value of long-term debt and RRB debt securities is based upon pricing models that incorporate quoted market prices for those issues or similar issues adjusted for market conditions, credit ratings of the respective companies and treasury benchmark yields. The fair values provided in the table below are classified as Level 2 within the fair value hierarchy. Carrying amounts and estimated fair values are as follows: Eversource CL&P NSTAR Electric PSNH (Millions of Dollars) Carrying Fair Carrying Fair Carrying Fair Carrying Fair As of March 31, 2024: Preferred Stock Not Subject to Mandatory Redemption $ 155.6 $ 123.0 $ 116.2 $ 90.7 $ 43.0 $ 32.3 $ — $ — Long-Term Debt 25,795.2 23,895.8 4,953.9 4,615.2 4,498.0 4,186.0 1,682.7 1,508.4 Rate Reduction Bonds 388.9 369.3 — — — — 388.9 369.3 As of December 31, 2023: Preferred Stock Not Subject to Mandatory Redemption $ 155.6 $ 122.2 $ 116.2 $ 90.4 $ 43.0 $ 31.8 $ — $ — Long-Term Debt 24,413.5 22,855.2 4,814.4 4,572.0 4,496.9 4,273.7 1,431.6 1,292.6 Rate Reduction Bonds 410.5 395.0 — — — — 410.5 395.0 Derivative Instruments and Marketable Securities: Derivative instruments and investments in marketable securities are carried at fair value. For further information, see Note 4, "Derivative Instruments," and Note 5, "Marketable Securities," to the financial statements. See Note 1C, "Summary of Significant Accounting Policies – Fair Value Measurements," for the fair value measurement policy and the fair value hierarchy.

ACCUMULATED OTHER COMPREHENSIVE

ACCUMULATED OTHER COMPREHENSIVE INCOME/(LOSS)	3 Months Ended
ACCUMULATED OTHER COMPREHENSIVE INCOME/(LOSS)	Mar. 31, 2024
Equity [Abstract]
ACCUMULATED OTHER COMPREHENSIVE INCOME/(LOSS)	ACCUMULATED OTHER COMPREHENSIVE INCOME/(LOSS) The changes in accumulated other comprehensive income/(loss) by component, net of tax, are as follows: For the Three Months Ended March 31, 2024 For the Three Months Ended March 31, 2023 Eversource (Millions of Dollars) Qualified Defined Total Qualified Unrealized Defined Total Balance as of Beginning of Period $ (0.4) $ (33.3) $ (33.7) $ (0.4) $ (1.2) $ (37.8) $ (39.4) Amounts Reclassified from AOCI — 5.2 5.2 — 1.2 2.0 3.2 Net OCI — 5.2 5.2 — 1.2 2.0 3.2 Balance as of End of Period $ (0.4) $ (28.1) $ (28.5) $ (0.4) $ — $ (35.8) $ (36.2) Defined benefit plan OCI amounts reclassified from AOCI relate to the unamortized actuarial gains and losses and prior service costs on the defined benefit plans are amortized from AOCI into Other Income, Net over the average future employee service period.

COMMON SHARES

COMMON SHARES	3 Months Ended
COMMON SHARES	Mar. 31, 2024
Equity [Abstract]
COMMON SHARES	COMMON SHARES The following table sets forth the Eversource parent common shares and the shares of common stock of CL&P, NSTAR Electric and PSNH that were authorized and issued, as well as the respective per share par values: Shares Authorized as of March 31, 2024 and December 31, 2023 Issued as of Par Value March 31, 2024 December 31, 2023 Eversource $ 5 410,000,000 361,276,965 359,984,073 CL&P $ 10 24,500,000 6,035,205 6,035,205 NSTAR Electric $ 1 100,000,000 200 200 PSNH $ 1 100,000,000 301 301 Common Share Issuances and Equity Distribution Agreement: On May 11, 2022, Eversource entered into an equity distribution agreement pursuant to which it may offer and sell up to $1.2 billion of its common shares from time to time through an “at-the-market” (ATM) equity offering program. Eversource may issue and sell its common shares through its sales agents during the term of this agreement. Shares may be offered in transactions on the New York Stock Exchange, in the over-the-counter market, through negotiated transactions or otherwise. Sales may be made at either market prices prevailing at the time of sale, at prices related to such prevailing market prices or at negotiated prices. In the first quarter of 2024, Eversource issued 1,292,892 common shares, which resulted in proceeds of $75.4 million, net of issuance costs. Eversource used the net proceeds received for general corporate purposes. In 2023, no shares were issued under this agreement. Treasury Shares: As of March 31, 2024 and December 31, 2023, there were 9,897,551 and 10,443,807 Eversource common shares held as treasury shares, respectively. As of March 31, 2024 and December 31, 2023, there we re 351,379,414 and 349,540,266 Eversource common shares outstanding, respectively. Eversource issues treasury shares to satisfy awards under the Company's incentive plans, shares issued under the dividend reinvestment and share purchase plan, and matching contributions under the Eversource 401k Plan. The issuance of treasury shares represents a non-cash transaction, as the treasury shares were used to fulfill Eversource's obligations that require the issuance of common shares. Dividends on the preferred stock of CL&P and NSTAR Electric totaled $1.9 million for each of the three months ended March 31, 2024 and 2023. These dividends were presented as Net Income Attributable to Noncontrolling Interests on the Eversource statements of income. Noncontrolling Interest – Preferred Stock of Subsidiaries on the Eversource balance sheets totaled $155.6 million as of March 31, 2024 and December 31, 2023. On the Eversource balance sheets, Common Shareholders' Equity was fully attributable to Eversource parent and Noncontrolling Interest – Preferred Stock of Subsidiaries was fully attributable to the noncontrolling interest.

COMMON SHAREHOLDERS' EQUITY AND

COMMON SHAREHOLDERS' EQUITY AND NONCONTROLLING INTERESTS	3 Months Ended
COMMON SHAREHOLDERS' EQUITY AND NONCONTROLLING INTERESTS	Mar. 31, 2024
Equity [Abstract]
COMMON SHAREHOLDERS' EQUITY AND NONCONTROLLING INTERESTS	COMMON SHARES The following table sets forth the Eversource parent common shares and the shares of common stock of CL&P, NSTAR Electric and PSNH that were authorized and issued, as well as the respective per share par values: Shares Authorized as of March 31, 2024 and December 31, 2023 Issued as of Par Value March 31, 2024 December 31, 2023 Eversource $ 5 410,000,000 361,276,965 359,984,073 CL&P $ 10 24,500,000 6,035,205 6,035,205 NSTAR Electric $ 1 100,000,000 200 200 PSNH $ 1 100,000,000 301 301 Common Share Issuances and Equity Distribution Agreement: On May 11, 2022, Eversource entered into an equity distribution agreement pursuant to which it may offer and sell up to $1.2 billion of its common shares from time to time through an “at-the-market” (ATM) equity offering program. Eversource may issue and sell its common shares through its sales agents during the term of this agreement. Shares may be offered in transactions on the New York Stock Exchange, in the over-the-counter market, through negotiated transactions or otherwise. Sales may be made at either market prices prevailing at the time of sale, at prices related to such prevailing market prices or at negotiated prices. In the first quarter of 2024, Eversource issued 1,292,892 common shares, which resulted in proceeds of $75.4 million, net of issuance costs. Eversource used the net proceeds received for general corporate purposes. In 2023, no shares were issued under this agreement. Treasury Shares: As of March 31, 2024 and December 31, 2023, there were 9,897,551 and 10,443,807 Eversource common shares held as treasury shares, respectively. As of March 31, 2024 and December 31, 2023, there we re 351,379,414 and 349,540,266 Eversource common shares outstanding, respectively. Eversource issues treasury shares to satisfy awards under the Company's incentive plans, shares issued under the dividend reinvestment and share purchase plan, and matching contributions under the Eversource 401k Plan. The issuance of treasury shares represents a non-cash transaction, as the treasury shares were used to fulfill Eversource's obligations that require the issuance of common shares. Dividends on the preferred stock of CL&P and NSTAR Electric totaled $1.9 million for each of the three months ended March 31, 2024 and 2023. These dividends were presented as Net Income Attributable to Noncontrolling Interests on the Eversource statements of income. Noncontrolling Interest – Preferred Stock of Subsidiaries on the Eversource balance sheets totaled $155.6 million as of March 31, 2024 and December 31, 2023. On the Eversource balance sheets, Common Shareholders' Equity was fully attributable to Eversource parent and Noncontrolling Interest – Preferred Stock of Subsidiaries was fully attributable to the noncontrolling interest.

EARNINGS PER SHARE

EARNINGS PER SHARE	3 Months Ended
EARNINGS PER SHARE	Mar. 31, 2024
Earnings Per Share [Abstract]
EARNINGS PER SHARE	EARNINGS PER SHARE Basic EPS is computed based upon the weighted average number of common shares outstanding during each period. Diluted EPS is computed on the basis of the weighted average number of common shares outstanding plus the potential dilutive effect of certain share-based compensation awards as if they were converted into outstanding common shares. The dilutive effect of unvested RSU and performance share awards is calculated using the treasury stock method. RSU and performance share awards are included in basic weighted average common shares outstanding as of the date that all necessary vesting conditions have been satisfied. For the three months ended March 31, 2024 and 2023, there were no antidilutive share awards excluded from the computation of diluted EPS. The following table sets forth the components of basic and diluted EPS: Eversource (Millions of Dollars, except share information) For the Three Months Ended March 31, 2024 March 31, 2023 Net Income Attributable to Common Shareholders $ 521.8 $ 491.2 Weighted Average Common Shares Outstanding: Basic 350,717,114 349,217,147 Dilutive Effect 280,106 394,866 Diluted 350,997,220 349,612,013 Basic and Diluted EPS $ 1.49 $ 1.41

REVENUES

REVENUES	3 Months Ended
REVENUES	Mar. 31, 2024
Revenue from Contract with Customer [Abstract]
REVENUES	REVENUES The following tables present operating revenues disaggregated by revenue source: For the Three Months Ended March 31, 2024 Eversource (Millions of Dollars) Electric Natural Gas Electric Water Distribution Other Eliminations Total Revenues from Contracts with Customers Retail Tariff Sales Residential $ 1,254.1 $ 507.6 $ — $ 30.3 $ — $ — $ 1,792.0 Commercial 707.5 247.1 — 16.2 — (1.7) 969.1 Industrial 87.7 59.8 — 1.0 — (5.1) 143.4 Total Retail Tariff Sales Revenues 2,049.3 814.5 — 47.5 — (6.8) 2,904.5 Wholesale Transmission Revenues — — 474.1 — — (361.6) 112.5 Wholesale Market Sales Revenues 165.3 58.2 — 0.9 — — 224.4 Other Revenues from Contracts with Customers 28.4 1.1 3.9 (0.2) 443.6 (441.4) 35.4 Total Revenues from Contracts with Customers 2,243.0 873.8 478.0 48.2 443.6 (809.8) 3,276.8 Alternative Revenue Programs 13.2 31.5 29.6 1.6 — (26.8) 49.1 Other Revenues 5.5 0.7 0.2 0.3 — — 6.7 Total Operating Revenues $ 2,261.7 $ 906.0 $ 507.8 $ 50.1 $ 443.6 $ (836.6) $ 3,332.6 For the Three Months Ended March 31, 2023 Eversource (Millions of Dollars) Electric Natural Gas Electric Water Distribution Other Eliminations Total Revenues from Contracts with Customers Retail Tariff Sales Residential $ 1,464.0 $ 576.6 $ — $ 28.9 $ — $ — $ 2,069.5 Commercial 788.4 320.0 — 15.5 — (1.0) 1,122.9 Industrial 89.1 69.6 — 1.1 — (5.1) 154.7 Total Retail Tariff Sales Revenues 2,341.5 966.2 — 45.5 — (6.1) 3,347.1 Wholesale Transmission Revenues — — 435.0 — — (325.3) 109.7 Wholesale Market Sales Revenues 217.3 49.1 — 0.8 — — 267.2 Other Revenues from Contracts with Customers 18.3 1.5 4.7 2.1 413.8 (412.6) 27.8 Total Revenues from Contracts with Customers 2,577.1 1,016.8 439.7 48.4 413.8 (744.0) 3,751.8 Alternative Revenue Programs 6.0 27.4 18.7 1.7 — (16.9) 36.9 Other Revenues 5.5 1.0 0.2 0.2 — — 6.9 Total Operating Revenues $ 2,588.6 $ 1,045.2 $ 458.6 $ 50.3 $ 413.8 $ (760.9) $ 3,795.6 For the Three Months Ended March 31, 2024 For the Three Months Ended March 31, 2023 (Millions of Dollars) CL&P NSTAR Electric PSNH CL&P NSTAR Electric PSNH Revenues from Contracts with Customers Retail Tariff Sales Residential $ 626.8 $ 462.2 $ 165.1 $ 762.2 $ 467.8 $ 234.0 Commercial 252.4 373.5 82.0 295.3 384.3 108.6 Industrial 33.3 29.9 24.5 33.9 32.6 22.6 Total Retail Tariff Sales Revenues 912.5 865.6 271.6 1,091.4 884.7 365.2 Wholesale Transmission Revenues 200.7 188.8 84.6 195.8 167.8 71.4 Wholesale Market Sales Revenues 121.2 31.6 12.5 154.6 41.1 21.6 Other Revenues from Contracts with Customers 16.4 11.1 5.2 10.0 10.8 2.9 Total Revenues from Contracts with Customers 1,250.8 1,097.1 373.9 1,451.8 1,104.4 461.1 Alternative Revenue Programs 27.4 7.8 7.6 24.6 (9.5) 9.6 Other Revenues 2.9 2.0 0.8 2.2 2.5 1.0 Eliminations (159.8) (159.3) (56.2) (139.7) (141.1) (51.5) Total Operating Revenues $ 1,121.3 $ 947.6 $ 326.1 $ 1,338.9 $ 956.3 $ 420.2

SEGMENT INFORMATION

SEGMENT INFORMATION	3 Months Ended
SEGMENT INFORMATION	Mar. 31, 2024
Segment Reporting [Abstract]
SEGMENT INFORMATION	SEGMENT INFORMATION Eversource is organized into the Electric Distribution, Electric Transmission, Natural Gas Distribution and Water Distribution reportable segments and Other based on a combination of factors, including the characteristics of each segments' services, the sources of operating revenues and expenses and the regulatory environment in which each segment operates. These reportable segments represent substantially all of Eversource's total consolidated revenues. Revenues from the sale of electricity, natural gas and water primarily are derived from residential, commercial and industrial customers and are not dependent on any single customer. The Electric Distribution reportable segment includes the results of NSTAR Electric's solar power facilities. Eversource's reportable segments are determined based upon the level at which Eversource's chief operating decision maker assesses performance and makes decisions about the allocation of company resources. The remainder of Eversource's operations is presented as Other in the tables below and primarily consists of 1) the equity in earnings of Eversource parent from its subsidiaries and intercompany interest income, both of which are eliminated in consolidation, and interest expense related to the debt of Eversource parent, 2) the revenues and expenses of Eversource Service, most of which are eliminated in consolidation, 3) the operations of CYAPC and YAEC, 4) the results of other unregulated subsidiaries, which are not part of its core business, and 5) Eversource parent's equity ownership interests that are not consolidated, which primarily include the offshore wind business, a natural gas pipeline owned by Enbridge, Inc., and a renewable energy investment fund that was liquidated in the first quarter of 2023. In the ordinary course of business, Yankee Gas, NSTAR Gas and EGMA purchase natural gas transmission services from the Enbridge, Inc. natural gas pipeline project described above. These affiliate transaction costs total $77.7 million annually and are classified as Purchased Power, Purchased Natural Gas and Transmission on the Eversource statements of income. Each of Eversource's subsidiaries, including CL&P, NSTAR Electric and PSNH, has one reportable segment. Cash flows used for investments in plant included in the segment information below are cash capital expenditures that do not include amounts incurred on capital projects but not yet paid, cost of removal, AFUDC related to equity funds, and the capitalized and deferred portions of pension and PBOP income/expense. Eversource's segment information is as follows: For the Three Months Ended March 31, 2024 Eversource (Millions of Dollars) Electric Distribution Natural Gas Distribution Electric Transmission Water Distribution Other Eliminations Total Operating Revenues $ 2,261.7 $ 906.0 $ 507.8 $ 50.1 $ 443.6 $ (836.6) $ 3,332.6 Depreciation and Amortization (109.8) (83.0) (101.0) (0.6) (45.7) 2.5 (337.6) Other Operating Expenses (1,905.1) (554.6) (141.9) (32.0) (349.5) 834.1 (2,149.0) Operating Income $ 246.8 $ 268.4 $ 264.9 $ 17.5 $ 48.4 $ — $ 846.0 Interest Expense $ (82.5) $ (24.5) $ (40.9) $ (11.4) $ (146.1) $ 54.7 $ (250.7) Other Income, Net 56.6 10.1 14.1 1.7 622.6 (614.1) 91.0 Net Income Attributable to Common Shareholders 168.1 190.6 176.7 5.4 540.4 (559.4) 521.8 Cash Flows Used for Investments in Plant 471.3 244.8 358.4 31.9 43.0 — 1,149.4 For the Three Months Ended March 31, 2023 Eversource (Millions of Dollars) Electric Natural Gas Electric Water Distribution Other Eliminations Total Operating Revenues $ 2,588.6 $ 1,045.2 $ 458.6 $ 50.3 $ 413.8 $ (760.9) $ 3,795.6 Depreciation and Amortization (22.0) (77.0) (89.9) (13.3) (36.8) 2.1 (236.9) Other Operating Expenses (2,342.3) (730.4) (128.2) (27.9) (339.6) 759.3 (2,809.1) Operating Income $ 224.3 $ 237.8 $ 240.5 $ 9.1 $ 37.4 $ 0.5 $ 749.6 Interest Expense $ (69.3) $ (21.2) $ (41.5) $ (9.4) $ (85.1) $ 32.0 $ (194.5) Other Income, Net 54.3 9.0 9.4 1.1 565.8 (550.6) 89.0 Net Income Attributable to Common Shareholders 165.5 170.3 155.1 1.5 516.9 (518.1) 491.2 Cash Flows Used for Investments in Plant 371.9 165.5 336.6 37.9 65.2 — 977.1 The following table summarizes Eversource's segmented total assets: Eversource (Millions of Dollars) Electric Natural Gas Electric Water Distribution Other Eliminations Total As of March 31, 2024 $ 30,437.0 $ 8,948.5 $ 15,129.8 $ 2,972.2 $ 28,358.1 $ (28,523.4) $ 57,322.2 As of December 31, 2023 29,426.4 8,775.3 14,806.5 2,944.8 26,337.7 (26,678.5) 55,612.2

Insider Trading Arrangements

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

SUMMARY OF SIGNIFICANT ACCOUN_2

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Policies)	3 Months Ended
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Policies)	Mar. 31, 2024
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation Eversource Energy is a public utility holding company primarily engaged, through its wholly-owned regulated utility subsidiaries, in the energy delivery business. Eversource Energy's wholly-owned regulated utility subsidiaries consist of CL&P, NSTAR Electric and PSNH (electric utilities), Yankee Gas, NSTAR Gas and EGMA (natural gas utilities), and Aquarion (water utilities). Eversource provides energy delivery and/or water service to approximately 4.4 million electric, natural gas and water customers through twelve regulated utilities in Connecticut, Massachusetts and New Hampshire. The unaudited condensed consolidated financial statements of Eversource, NSTAR Electric and PSNH include the accounts of each of their respective subsidiaries. Intercompany transactions have been eliminated in consolidation. The accompanying unaudited condensed consolidated financial statements of Eversource, NSTAR Electric and PSNH and the unaudited condensed financial statements of CL&P are herein collectively referred to as the "financial statements." The combined notes to the financial statements have been prepared pursuant to the rules and regulations of the SEC. Certain information and footnote disclosures included in annual financial statements prepared in accordance with GAAP have been omitted pursuant to such rules and regulations. The accompanying financial statements should be read in conjunction with the Combined Notes to Financial Statements included in Item 8, "Financial Statements and Supplementary Data," of the Eversource 2023 Form 10-K, which was filed with the SEC on February 14, 2024. The preparation of the financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and the disclosure of contingent liabilities as of the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates. The financial statements contain, in the opinion of management, all adjustments (including normal, recurring adjustments) necessary to present fairly Eversource's, CL&P's, NSTAR Electric's and PSNH's financial position as of March 31, 2024 and December 31, 2023, and the results of operations, comprehensive income, common shareholders' equity and cash flows for the three months ended March 31, 2024 and 2023. The results of operations, comprehensive income and cash flows for the three months ended March 31, 2024 and 2023 are not necessarily indicative of the results expected for a full year. CYAPC and YAEC are inactive regional nuclear power companies engaged in the long-term storage of their spent nuclear fuel. Eversource consolidates the operations of CYAPC and YAEC because CL&P's, NSTAR Electric's and PSNH's combined ownership and voting interests in each of these entities is greater than 50 percent. Intercompany transactions between CL&P, NSTAR Electric, PSNH and the CYAPC and YAEC companies have been eliminated in consolidation of the Eversource financial statements. Eversource holds several equity ownership interests that are not consolidated and are accounted for under the equity method, including 50 percent ownership interests in three offshore wind projects and a tax equity investment in one of the projects. See Note 1E, "Summary of Significant Accounting Policies – Investments in Unconsolidated Affiliates," for further information on Eversource’s equity method investments. Eversource's utility subsidiaries' electric, natural gas and water distribution and transmission businesses are subject to rate-regulation that is based on cost recovery and meets the criteria for application of accounting guidance for entities with rate-regulated operations, which considers the effect of regulation on the differences in the timing of the recognition of certain revenues and expenses from those of other businesses and industries. See Note 2, "Regulatory Accounting," for further information. Certain reclassifications of prior period data were made in the accompanying financial statements to conform to the current period presentation.
Allowance for Uncollectible Accounts	Allowance for Uncollectible Accounts Receivables, Net on the balance sheets primarily includes trade receivables from retail customers and customers related to wholesale transmission contracts, wholesale market sales, sales of RECs, and property rentals. Receivables, Net also includes customer receivables for the purchase of electricity from a competitive third party supplier, the current portion of customer energy efficiency loans, property damage receivables and other miscellaneous receivables. There is no material concentration of receivables. Receivables are recorded at amortized cost, net of a credit loss provision (or allowance for uncollectible accounts). The current expected credit loss (CECL) model is applied to receivables for purposes of calculating the allowance for uncollectible accounts. This model is based on expected losses and results in the recognition of estimated expected credit losses, including uncollectible amounts for both billed and unbilled revenues, over the life of the receivable at the time a receivable is recorded. The allowance for uncollectible accounts is determined based upon a variety of judgments and factors, including an aging-based quantitative assessment that applies an estimated uncollectible percentage to each receivable aging category. Factors in determining credit loss include historical collection, write-off experience, analysis of delinquency statistics, and management's assessment of collectability from customers, including current economic conditions, customer payment trends, the impact on customer bills because of energy usage trends and changes in rates, flexible payment plans and financial hardship arrearage management programs offered to customers, reasonable forecasts, and expectations of future collectability and collection efforts. Management continuously assesses the collectability of receivables and adjusts estimates based on actual experience and future expectations based on economic conditions, collection efforts and other factors. Management also monitors the aging analysis of receivables to determine if there are changes in the collections of accounts receivable. Receivable balances are written off against the allowance for uncollectible accounts when the customer accounts are no longer in service and these balances are deemed to be uncollectible. Management concluded that the reserve balance as of March 31, 2024 adequately reflected the collection risk and net realizable value for its receivables. The PURA allows CL&P and Yankee Gas to accelerate the recovery of accounts receivable balances attributable to qualified customers under financial or medical duress (uncollectible hardship accounts receivable) outstanding for greater than 180 days and 90 days, respectively. The DPU allows NSTAR Electric, NSTAR Gas and EGMA to recover in rates amounts associated with certain uncollectible hardship accounts receivable. These uncollectible hardship customer account balances are included in Regulatory Assets or Other Long-Term Assets on the balance sheets. Hardship customers are protected from shut-off in certain circumstances, and historical collection experience has reflected a higher default risk as compared to the rest of the receivable population. Management uses a higher credit risk profile for this pool of trade receivables as compared to non-hardship receivables. The allowance for uncollectible hardship accounts is included in the total uncollectible allowance balance.
Fair Value Measurements	Fair Value Measurements Fair value measurement guidance is applied to derivative contracts that are not elected or designated as "normal purchases" or "normal sales" (normal) and to marketable securities held in trusts. Fair value measurement guidance is also applied to valuations of the investments used to calculate the funded status of pension and PBOP plans, the nonrecurring fair value measurements of nonfinancial assets such as goodwill, long-lived assets, equity method investments, AROs, and in the valuation of business combinations and asset acquisitions. The fair value measurement guidance was also applied in estimating the fair value of preferred stock, long-term debt and RRBs. Fair Value Hierarchy: In measuring fair value, Eversource uses observable market data when available in order to minimize the use of unobservable inputs. Inputs used in fair value measurements are categorized into three fair value hierarchy levels for disclosure purposes. The entire fair value measurement is categorized based on the lowest level of input that is significant to the fair value measurement. Eversource evaluates the classification of assets and liabilities measured at fair value on a quarterly basis. The levels of the fair value hierarchy are described below: Level 1 - Inputs are quoted prices (unadjusted) in active markets for identical assets or liabilities as of the reporting date. Active markets are those in which transactions for the asset or liability occur in sufficient frequency and volume to provide pricing information on an ongoing basis. Level 2 - Inputs are quoted prices for similar instruments in active markets, quoted prices for identical or similar instruments in markets that are not active, and model-derived valuations in which all significant inputs are observable. Level 3 - Quoted market prices are not available. Fair value is derived from valuation techniques in which one or more significant inputs or assumptions are unobservable. Where possible, valuation techniques incorporate observable market inputs that can be validated to external sources such as industry exchanges, including prices of energy and energy-related products. Uncategorized - Investments that are measured at net asset value are not categorized within the fair value hierarchy.
Other Taxes	Other TaxesEversource's companies that serve customers in Connecticut collect gross receipts taxes levied by the state of Connecticut from their customers. These gross receipts taxes are recorded separately with collections in Operating Revenues and with payments in Taxes Other Than Income Taxes on the statements of incomeAs agents for state and local governments, Eversource's companies that serve customers in Connecticut and Massachusetts collect certain sales taxes that are recorded on a net basis with no impact on the statements of income.

SUMMARY OF SIGNIFICANT ACCOUN_3

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Tables)	3 Months Ended
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Tables)	Mar. 31, 2024
Accounting Policies [Abstract]
Allowance for Uncollectible Accounts	The activity in the allowance for uncollectible accounts by portfolio segment as of March 31 st is as follows: Eversource CL&P NSTAR Electric PSNH (Millions of Dollars) Hardship Accounts Retail (Non-Hardship), Total Allowance Hardship Accounts Retail (Non-Hardship), Total Allowance Hardship Accounts Retail (Non-Hardship), Total Allowance Total Allowance Three Months Ended 2024 Beginning Balance $ 366.8 $ 187.7 $ 554.5 $ 259.7 $ 36.3 $ 296.0 $ 43.6 $ 53.4 $ 97.0 $ 14.3 Uncollectible Expense — 16.4 16.4 — 3.5 3.5 — 6.1 6.1 1.2 Uncollectible Costs Deferred (1) 27.5 11.4 38.9 22.7 2.7 25.4 (0.8) 4.4 3.6 1.3 Write-Offs (15.1) (28.5) (43.6) (10.8) (7.7) (18.5) (1.0) (9.2) (10.2) (3.2) Recoveries Collected 0.2 3.7 3.9 0.2 1.2 1.4 — 1.2 1.2 0.2 Ending Balance $ 379.4 $ 190.7 $ 570.1 $ 271.8 $ 36.0 $ 307.8 $ 41.8 $ 55.9 $ 97.7 $ 13.8 Eversource CL&P NSTAR Electric PSNH (Millions of Dollars) Hardship Accounts Retail (Non-Hardship), Total Allowance Hardship Accounts Retail (Non-Hardship), Total Allowance Hardship Accounts Retail (Non-Hardship), Total Allowance Total Allowance Three Months Ended 2023 Beginning Balance $ 284.4 $ 201.9 $ 486.3 $ 188.9 $ 36.4 $ 225.3 $ 43.7 $ 51.3 $ 95.0 $ 29.2 Uncollectible Expense — 22.8 22.8 — 3.9 3.9 — 4.7 4.7 5.1 Uncollectible Costs Deferred (1) 43.7 14.3 58.0 34.3 2.7 37.0 (1.3) 5.4 4.1 1.2 Write-Offs (9.7) (26.3) (36.0) (7.3) (7.0) (14.3) (0.4) (10.3) (10.7) (2.2) Recoveries Collected 0.3 3.7 4.0 0.3 1.2 1.5 — 1.5 1.5 0.2 Ending Balance $ 318.7 $ 216.4 $ 535.1 $ 216.2 $ 37.2 $ 253.4 $ 42.0 $ 52.6 $ 94.6 $ 33.5 (1)
Components of Other Income, Net	The components of Other Income, Net on the statements of income were as follows: For the Three Months Ended March 31, 2024 March 31, 2023 (Millions of Dollars) Eversource CL&P NSTAR Electric PSNH Eversource CL&P NSTAR Electric PSNH Pension, SERP and PBOP Non-Service $ 27.8 $ 6.5 $ 12.3 $ 3.6 $ 34.8 $ 9.5 $ 14.7 $ 4.2 AFUDC Equity 26.8 6.0 16.2 1.9 15.5 4.1 9.5 0.7 Equity in Earnings of Unconsolidated Affiliates 7.8 — 0.2 — 3.8 — 0.1 — Investment (Loss)/Income (0.8) (0.7) 0.4 (0.2) (1.7) (0.6) (0.5) (0.1) Interest Income 30.0 4.7 18.0 1.8 23.1 1.9 16.0 0.9 Other (1) (0.6) — — — 13.5 — 0.1 — Total Other Income, Net $ 91.0 $ 16.5 $ 47.1 $ 7.1 $ 89.0 $ 14.9 $ 39.9 $ 5.7 (1) Eversource’s equity method investment in a renewable energy fund was liquidated in March 2023. Liquidation proceeds in excess of the carrying value were recorded in 2023 within Other in the table above. See Note 1E, "Summary of Significant Accounting Policies - Investments in Unconsolidated Affiliates," for further information.
Investments in Unconsolidated Affiliates	Eversource's investments included the following: Investment Balance (Millions of Dollars) Ownership Interest As of March 31, 2024 As of December 31, 2023 Offshore Wind Business 50% - 100% $ 596.4 $ 515.5 Natural Gas Pipeline - Algonquin Gas Transmission, LLC 15% 115.9 116.0 Other various 29.4 29.0 Total Investments in Unconsolidated Affiliates $ 741.7 $ 660.5
Other Taxes	These gross receipts taxes are recorded separately with collections in Operating Revenues and with payments in Taxes Other Than Income Taxes on the statements of income as follows: For the Three Months Ended (Millions of Dollars) March 31, 2024 March 31, 2023 Eversource $ 53.3 $ 55.0 CL&P 43.9 43.1
Non-cash Investing Activities	Non-cash investing activities include plant additions included in Accounts Payable as follows: (Millions of Dollars) As of March 31, 2024 As of March 31, 2023 Eversource $ 453.6 $ 400.8 CL&P 112.8 101.9 NSTAR Electric 132.7 117.4 PSNH 75.2 54.6
Reconciliation of Cash Balances to Cash and Restricted Cash	The following table reconciles cash as reported on the balance sheets to the cash and restricted cash balance as reported on the statements of cash flows: As of March 31, 2024 As of December 31, 2023 (Millions of Dollars) Eversource CL&P NSTAR Electric PSNH Eversource CL&P NSTAR Electric PSNH Cash as reported on the Balance Sheets $ 259.2 $ 29.0 $ 20.2 $ 14.1 $ 53.9 $ 10.2 $ 6.7 $ 0.2 Restricted cash included in: Special Deposits 68.7 2.1 16.3 17.0 81.5 2.0 16.1 31.6 Marketable Securities 16.0 — — — 13.7 — — — Other Long-Term Assets 16.5 — — 3.2 17.3 — — 3.2 Cash and Restricted Cash as reported on the Statements of Cash Flows $ 360.4 $ 31.1 $ 36.5 $ 34.3 $ 166.4 $ 12.2 $ 22.8 $ 35.0

REGULATORY ACCOUNTING (Tables)

REGULATORY ACCOUNTING (Tables)	3 Months Ended
REGULATORY ACCOUNTING (Tables)	Mar. 31, 2024
Regulated Operations [Abstract]
Components of Regulatory Assets	The components of regulatory assets were as follows: As of March 31, 2024 As of December 31, 2023 (Millions of Dollars) Eversource CL&P NSTAR PSNH Eversource CL&P NSTAR PSNH Storm Costs, Net $ 1,942.7 $ 957.6 $ 657.3 $ 327.8 $ 1,785.9 $ 896.6 $ 609.1 $ 280.2 Regulatory Tracking Mechanisms 1,541.2 593.5 522.3 184.9 1,319.2 354.5 482.9 182.2 Benefit Costs 1,098.1 194.5 330.2 78.0 1,117.3 197.4 336.7 79.3 Income Taxes, Net 925.7 517.5 133.6 15.5 912.4 512.6 128.6 16.4 Securitized Stranded Costs 381.7 — — 381.7 392.5 — — 392.5 Goodwill-related 259.9 — 223.1 — 264.1 — 226.7 — Asset Retirement Obligations 141.0 39.1 73.8 4.9 137.9 38.5 72.3 4.7 Derivative Liabilities 103.7 103.7 — — 120.9 120.9 — — Other Regulatory Assets 334.8 21.8 100.6 6.8 339.0 22.7 101.6 8.0 Total Regulatory Assets 6,728.8 2,427.7 2,040.9 999.6 6,389.2 2,143.2 1,957.9 963.3 Less: Current Portion 1,889.5 717.6 718.7 188.1 1,674.2 480.4 676.1 189.5 Total Long-Term Regulatory Assets $ 4,839.3 $ 1,710.1 $ 1,322.2 $ 811.5 $ 4,715.0 $ 1,662.8 $ 1,281.8 $ 773.8
Components of Regulatory Liabilities	The components of regulatory liabilities were as follows: As of March 31, 2024 As of December 31, 2023 (Millions of Dollars) Eversource CL&P NSTAR PSNH Eversource CL&P NSTAR PSNH EDIT due to Tax Cuts and Jobs Act of 2017 $ 2,537.0 $ 966.1 $ 899.5 $ 337.5 $ 2,548.6 $ 969.2 $ 905.1 $ 339.3 Regulatory Tracking Mechanisms 711.7 167.5 384.2 80.2 668.3 154.0 347.2 114.4 Cost of Removal 687.6 168.2 431.0 14.8 666.6 157.9 420.9 16.2 Deferred Portion of Non-Service Income 373.2 53.1 184.9 38.2 354.0 49.9 175.9 36.6 AFUDC - Transmission 135.5 58.5 77.0 — 124.3 56.1 68.2 — Benefit Costs 44.8 0.5 18.0 — 51.0 0.6 22.2 — Other Regulatory Liabilities 203.1 37.3 13.7 4.8 201.9 30.4 13.9 4.6 Total Regulatory Liabilities 4,692.9 1,451.2 2,008.3 475.5 4,614.7 1,418.1 1,953.4 511.1 Less: Current Portion 641.5 117.3 405.2 86.1 591.8 102.2 368.1 117.5 Total Long-Term Regulatory Liabilities $ 4,051.4 $ 1,333.9 $ 1,603.1 $ 389.4 $ 4,022.9 $ 1,315.9 $ 1,585.3 $ 393.6

PROPERTY, PLANT AND EQUIPMENT_2

PROPERTY, PLANT AND EQUIPMENT AND ACCUMULATED DEPRECIATION (Tables)	3 Months Ended
	Mar. 31, 2024
Property, Plant and Equipment [Abstract]
Summary of Property, Plant, and Equipment	The following tables summarize property, plant and equipment by asset category: Eversource As of March 31, 2024 As of December 31, 2023 (Millions of Dollars) Distribution - Electric $ 19,929.5 $ 19,656.5 Distribution - Natural Gas 8,234.7 8,155.3 Transmission - Electric 15,182.6 14,666.8 Distribution - Water 2,294.9 2,280.1 Solar 201.1 201.1 Utility 45,842.8 44,959.8 Other (1) 2,069.3 2,006.8 Property, Plant and Equipment, Gross 47,912.1 46,966.6 Less: Accumulated Depreciation Utility (9,835.7) (9,670.1) Other (916.2) (869.6) Total Accumulated Depreciation (10,751.9) (10,539.7) Property, Plant and Equipment, Net 37,160.2 36,426.9 Construction Work in Progress 3,129.2 3,071.7 Total Property, Plant and Equipment, Net $ 40,289.4 $ 39,498.6 As of March 31, 2024 As of December 31, 2023 (Millions of Dollars) CL&P NSTAR PSNH CL&P NSTAR PSNH Distribution - Electric $ 8,003.9 $ 9,138.5 $ 2,827.4 $ 7,897.1 $ 9,000.5 $ 2,799.2 Transmission - Electric 6,609.2 6,014.5 2,560.5 6,548.2 5,630.8 2,489.5 Solar — 201.1 — — 201.1 — Property, Plant and Equipment, Gross 14,613.1 15,354.1 5,387.9 14,445.3 14,832.4 5,288.7 Less: Accumulated Depreciation (2,707.9) (3,648.7) (1,004.7) (2,670.5) (3,585.9) (984.0) Property, Plant and Equipment, Net 11,905.2 11,705.4 4,383.2 11,774.8 11,246.5 4,304.7 Construction Work in Progress 627.3 1,334.9 324.4 565.4 1,507.3 270.0 Total Property, Plant and Equipment, Net $ 12,532.5 $ 13,040.3 $ 4,707.6 $ 12,340.2 $ 12,753.8 $ 4,574.7 (1) These assets are primarily comprised of computer software, hardware and equipment at Eversource Service and buildings at The Rocky River Realty Company.

DERIVATIVE INSTRUMENTS (Tables)

DERIVATIVE INSTRUMENTS (Tables)	3 Months Ended
DERIVATIVE INSTRUMENTS (Tables)	Mar. 31, 2024
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Gross Fair Values and Net Amounts of Contracts	The following table presents the gross fair values of contracts, categorized by risk type, and the net amounts recorded as current or long-term derivative assets or liabilities: As of March 31, 2024 As of December 31, 2023 CL&P (Millions of Dollars) Fair Value Hierarchy Commodity Supply and Price Risk Netting (1) Net Amount Commodity Supply and Price Risk Netting (1) Net Amount Current Derivative Assets Level 2 $ 15.8 $ (0.4) $ 15.4 $ 16.4 $ (0.5) $ 15.9 Long-Term Derivative Assets Level 2 9.9 (0.4) 9.5 13.6 (0.5) 13.1 Current Derivative Liabilities Level 2 (79.2) — (79.2) (81.9) — (81.9) Long-Term Derivative Liabilities Level 2 (49.4) — (49.4) (68.0) — (68.0) (1) Amounts represent derivative assets and liabilities that Eversource elected to record net on the balance sheets. These amounts are subject to master netting agreements or similar agreements for which the right of offset exists.
Changes in the Level 3 Category of Derivative Assets Measured at Fair Value on a Recurring Basis	The following table presents changes in the Level 3 category of derivative assets and derivative liabilities measured at fair value on a recurring basis. The derivative assets and liabilities are presented on a net basis. CL&P For the Three Months Ended March 31, 2023 (Millions of Dollars) Derivatives, Net: Fair Value as of Beginning of Period $ (181.8) Net Realized/Unrealized Losses Included in Regulatory Assets (1.9) Settlements 14.9 Fair Value as of End of Period $ (168.8)

MARKETABLE SECURITIES (Tables)

MARKETABLE SECURITIES (Tables)	3 Months Ended
MARKETABLE SECURITIES (Tables)	Mar. 31, 2024
Investments, Debt and Equity Securities [Abstract]
Summary of Available-for-Sale Debt Securities	The following is a summary of the available-for-sale debt securities: As of March 31, 2024 As of December 31, 2023 Eversource (Millions of Dollars) Amortized Cost Pre-Tax Pre-Tax Fair Value Amortized Cost Pre-Tax Pre-Tax Fair Value Debt Securities $ 170.5 $ 0.2 $ (8.7) $ 162.0 $ 169.5 $ 1.4 $ (6.6) $ 164.3
Contractual Maturities of Available-for-Sale Debt Securities	As of March 31, 2024, the contractual maturities of available-for-sale debt securities were as follows: Eversource (Millions of Dollars) Amortized Cost Fair Value Less than one year $ 19.4 $ 19.4 One to five years 31.5 31.0 Six to ten years 37.7 36.4 Greater than ten years 81.9 75.2 Total Debt Securities $ 170.5 $ 162.0
Marketable Securities Recorded at Fair Value on a Recurring Basis by Level	The following table presents the marketable securities recorded at fair value on a recurring basis by the level in which they are classified within the fair value hierarchy: Eversource (Millions of Dollars) As of March 31, 2024 As of December 31, 2023 Level 1: Mutual Funds and Equities $ 176.0 $ 176.9 Money Market Funds 16.0 13.7 Total Level 1 $ 192.0 $ 190.6 Level 2: U.S. Government Issued Debt Securities (Agency and Treasury) $ 89.2 $ 90.1 Corporate Debt Securities 34.2 34.0 Asset-Backed Debt Securities 5.4 5.6 Municipal Bonds 7.3 9.8 Other Fixed Income Securities 9.9 11.1 Total Level 2 $ 146.0 $ 150.6 Total Marketable Securities $ 338.0 $ 341.2

SHORT-TERM AND LONG-TERM DEBT (

SHORT-TERM AND LONG-TERM DEBT (Tables)	3 Months Ended
SHORT-TERM AND LONG-TERM DEBT (Tables)	Mar. 31, 2024
Debt Disclosure [Abstract]
Borrowings Outstanding and Available under the Commercial Paper Programs	The amount of borrowings outstanding and available under the commercial paper programs were as follows: Borrowings Outstanding as of Available Borrowing Capacity as of Weighted-Average Interest Rate as of March 31, 2024 December 31, 2023 March 31, 2024 December 31, 2023 March 31, 2024 December 31, 2023 (Millions of Dollars) Eversource Parent Commercial Paper Program $ 1,934.9 $ 1,771.9 $ 65.1 $ 228.1 5.66 % 5.60 % NSTAR Electric Commercial Paper Program 419.0 365.8 231.0 284.2 5.38 % 5.40 %
Summary of Long-Term Debt Issuance and Repayments	The following table summarizes long-term debt issuances and repayments: (Millions of Dollars) Interest Rate Issuance/(Repayment) Issue Date or Repayment Date Maturity Date Use of Proceeds for Issuance/ CL&P 2024 Series A First Mortgage Bonds 4.65 % $ 350.0 January 2024 January 2029 Repaid short-term debt, paid capital expenditures and working capital PSNH Series X First Mortgage Bonds 5.35 % 300.0 April 2024 October 2033 Repaid short-term debt, paid capital expenditures and working capital Eversource Parent Series DD Senior Notes 5.00 % 350.0 January 2024 January 2027 Repaid short-term debt Eversource Parent Series EE Senior Notes 5.50 % 650.0 January 2024 January 2034 Repaid short-term debt Eversource Parent Series FF Senior Notes 5.85 % 700.0 April 2024 April 2031 Repay Series X Senior Notes and Aquarion’s 2014 Senior Notes at maturity and short-term debt Eversource Parent Series GG Senior Notes 5.95 % 700.0 April 2024 July 2034 Repay Series X Senior Notes and Aquarion’s 2014 Senior Notes at maturity and short-term debt

RATE REDUCTION BONDS AND VARI_2

RATE REDUCTION BONDS AND VARIABLE INTEREST ENTITIES (Tables)	3 Months Ended
	Mar. 31, 2024
Rate Reduction Bonds and Variable Interest Entity [Abstract]
Summary of the Impact of Funding on the Balance Sheets and Income Statements	The following tables summarize the impact of PSNH Funding on PSNH's balance sheets and income statements: (Millions of Dollars) PSNH Balance Sheets: As of March 31, 2024 As of December 31, 2023 Restricted Cash - Current Portion (included in Special Deposits) $ 15.5 $ 30.0 Restricted Cash - Long-Term Portion (included in Other Long-Term Assets) 3.2 3.2 Securitized Stranded Cost (included in Regulatory Assets) 381.7 392.5 Other Regulatory Liabilities (included in Regulatory Liabilities) 5.7 5.3 Accrued Interest (included in Other Current Liabilities) 2.4 6.3 Rate Reduction Bonds - Current Portion 43.2 43.2 Rate Reduction Bonds - Long-Term Portion 345.7 367.3 (Millions of Dollars) PSNH Income Statements: For the Three Months Ended March 31, 2024 March 31, 2023 Amortization of RRB Principal (included in Amortization of Regulatory Assets/(Liabilities), Net) $ 10.8 $ 10.8 Interest Expense on RRB Principal (included in Interest Expense) 3.7 4.1

PENSION BENEFITS AND POSTRETI_2

PENSION BENEFITS AND POSTRETIREMENT BENEFITS OTHER THAN PENSION (Tables)	3 Months Ended
	Mar. 31, 2024
Postemployment Benefits [Abstract]
Components of Net Periodic Benefit Expense/(Income)	Pension, SERP and PBOP expense reflected in the statements of cash flows for CL&P, NSTAR Electric and PSNH does not include intercompany allocations of net periodic benefit plan expense/(income), as these amounts are cash settled on a short-term basis. Pension and SERP PBOP For the Three Months Ended March 31, 2024 For the Three Months Ended March 31, 2024 (Millions of Dollars) Eversource CL&P NSTAR PSNH Eversource CL&P NSTAR PSNH Service Cost $ 10.8 $ 2.9 $ 2.1 $ 1.0 $ 1.7 $ 0.3 $ 0.3 $ 0.1 Interest Cost 62.0 12.4 13.1 6.7 8.0 1.4 2.2 0.9 Expected Return on Plan Assets (115.6) (23.3) (28.3) (12.2) (20.4) (2.4) (9.9) (1.4) Actuarial Loss/(Gain) 19.8 2.5 6.4 1.1 (0.1) — — — Prior Service Cost/(Credit) 0.3 — 0.1 — (5.4) 0.3 (4.2) 0.1 Settlement Loss 4.3 — — — — — — — Total Net Periodic Benefit Plan Income $ (18.4) $ (5.5) $ (6.6) $ (3.4) $ (16.2) $ (0.4) $ (11.6) $ (0.3) Intercompany Expense/(Income) Allocations N/A $ 0.3 $ 0.4 $ 0.1 N/A $ (0.6) $ (0.7) $ (0.2) Pension and SERP PBOP For the Three Months Ended March 31, 2023 For the Three Months Ended March 31, 2023 (Millions of Dollars) Eversource CL&P NSTAR PSNH Eversource CL&P NSTAR PSNH Service Cost $ 11.0 $ 3.0 $ 2.1 $ 1.1 $ 1.8 $ 0.3 $ 0.3 $ 0.2 Interest Cost 63.7 12.6 13.5 6.8 8.5 1.6 2.3 0.9 Expected Return on Plan Assets (115.9) (23.4) (28.4) (12.3) (19.1) (2.4) (9.2) (1.4) Actuarial Loss 12.5 0.8 4.9 0.4 — — — — Prior Service Cost/(Credit) 0.3 — 0.1 — (5.4) 0.3 (4.2) 0.1 Total Net Periodic Benefit Plan Income $ (28.4) $ (7.0) $ (7.8) $ (4.0) $ (14.2) $ (0.2) $ (10.8) $ (0.2) Intercompany Income Allocations N/A $ (2.0) $ (1.7) $ (0.5) N/A $ (0.5) $ (0.6) $ (0.2)

COMMITMENTS AND CONTINGENCIES (

COMMITMENTS AND CONTINGENCIES (Tables)	3 Months Ended
COMMITMENTS AND CONTINGENCIES (Tables)	Mar. 31, 2024
Commitments and Contingencies Disclosure [Abstract]
Environmental Sites and Related Reserves	The number of environmental sites and related reserves for which remediation or long-term monitoring, preliminary site work or site assessment is being performed are as follows: As of March 31, 2024 As of December 31, 2023 Number of Sites Reserve Number of Sites Reserve Eversource 66 $ 128.0 65 $ 128.2 CL&P 16 13.8 16 13.8 NSTAR Electric 13 5.9 12 5.4 PSNH 8 7.7 8 7.6
Summary of Exposure to Guarantees and Indemnifications	The following table summarizes Eversource parent's exposure to guarantees and indemnifications of its subsidiaries and affiliates to external parties, and primarily relates to its offshore wind business: As of March 31, 2024 Company (Obligor) Description Maximum Exposure North East Offshore, LLC, Sunrise Wind LLC, Revolution Wind, LLC and South Fork Wind, LLC Offshore wind construction-related purchase agreements with third-party contractors (1) $ 1,824.3 Eversource Investment LLC and South Fork Class B Member, LLC Funding and indemnification obligations of South Fork Wind and North East Offshore, LLC (2) 458.5 Sunrise Wind LLC OREC capacity production (3) 15.4 South Fork Wind, LLC Power Purchase Agreement Security (4) 7.1 Eversource Investment LLC Letters of Credit (5) 23.2 Eversource TEI LLC South Fork Wind Tax Equity (6) 50.0 Various Eversource subsidiaries Surety bonds (7) 38.8 Sunrise Wind LLC Surety bonds (8) 48.2 (1) Eversource parent issued guarantees on behalf of its 50 percent-owned affiliates, North East Offshore, LLC (NEO), Sunrise Wind LLC, Revolution Wind, LLC and South Fork Wind, LLC, under which Eversource parent agreed to guarantee each entity’s performance of obligations under certain construction-related purchase agreements with third-party contractors, in an aggregate amount not to exceed $3.02 billion. Eversource parent’s obligations under the guarantees expire upon the earlier of (i) dates ranging between May 2024 and October 2028 and (ii) full performance of the guaranteed obligations. Eversource parent also issued a separate guarantee to Ørsted on behalf of NEO, under which Eversource parent agreed to guarantee 50 percent of NEO’s payment obligations under certain offshore wind project construction-related agreements with Ørsted in an aggregate amount not to exceed $62.5 million and expiring upon full performance of the guaranteed obligation. (2) Eversource parent issued guarantees on behalf of its wholly-owned subsidiary Eversource Investment LLC (EI), which holds Eversource's investments in offshore wind-related equity method investments, and on behalf of its 50 percent-owned affiliate, South Fork Class B Member, LLC, whereby Eversource parent will guarantee each entity’s performance of certain capital expenditure funding obligations during the construction phases of the South Fork Wind project and NEO’s underlying offshore wind projects. Eversource parent also guaranteed certain indemnification obligations of EI associated with third party credit support for EI’s investment in NEO. These guarantees will not exceed $1.52 billion and expire upon the full performance of the guaranteed obligations. (3) Eversource parent issued a guarantee on behalf of its 50 percent-owned affiliate, Sunrise Wind LLC, whereby Eversource parent will guarantee Sunrise Wind LLC's performance of certain obligations, in an amount not to exceed $15.4 million, under the Offshore Wind Renewable Energy Certificate Purchase and Sale Agreement (the Agreement). The Agreement was executed by and between the New York State Energy Research and Development Authority (NYSERDA) and Sunrise Wind LLC. The guarantee expires upon the full performance of the guaranteed obligations. (4) Eversource parent issued a guarantee on behalf of its 50 percent-owned affiliate, South Fork Wind, LLC, whereby Eversource parent will guarantee South Fork Wind, LLC's performance of certain obligations, in an amount not to exceed $7.1 million, under a Power Purchase Agreement between the Long Island Power Authority and South Fork Wind, LLC (the Agreement). The guarantee expires upon the later of (i) the end of the Agreement term and (ii) full performance of the guaranteed obligations. (5) Eversource parent entered into a guarantee on behalf of EI, under which Eversource parent would guarantee EI's obligations under a letter of credit facility with a financial institution that EI may request in an aggregate amount of up to approximately $25 million. As of March 31, 2024, EI has issued letters of credit on behalf of South Fork Wind, LLC, Sunrise Wind LLC and Revolution Wind, LLC totaling $23.2 million. The guarantee will remain in effect until full performance of the guaranteed obligations. (6) Eversource parent issued a guarantee on behalf of its wholly-owned subsidiary, Eversource TEI LLC, whereby Eversource parent will guarantee Eversource TEI LLC’s performance of certain obligations, in an amount not to exceed $50.0 million, in connection with any remaining obligations under the LLC agreement. Eversource parent’s obligations expire upon the full performance of the guaranteed obligations. (7) Surety bonds expire in 2024 and 2025. Expiration dates reflect termination dates, the majority of which will be renewed or extended. Certain surety bonds contain credit ratings triggers that would require Eversource parent to post collateral in the event that the unsecured debt credit ratings of Eversource parent are downgraded. (8)

FAIR VALUE OF FINANCIAL INSTR_2

FAIR VALUE OF FINANCIAL INSTRUMENTS (Tables)	3 Months Ended
FAIR VALUE OF FINANCIAL INSTRUMENTS (Tables)	Mar. 31, 2024
Fair Value Disclosures [Abstract]
Carrying Amounts and Estimated Fair Values of Financial Instruments	Carrying amounts and estimated fair values are as follows: Eversource CL&P NSTAR Electric PSNH (Millions of Dollars) Carrying Fair Carrying Fair Carrying Fair Carrying Fair As of March 31, 2024: Preferred Stock Not Subject to Mandatory Redemption $ 155.6 $ 123.0 $ 116.2 $ 90.7 $ 43.0 $ 32.3 $ — $ — Long-Term Debt 25,795.2 23,895.8 4,953.9 4,615.2 4,498.0 4,186.0 1,682.7 1,508.4 Rate Reduction Bonds 388.9 369.3 — — — — 388.9 369.3 As of December 31, 2023: Preferred Stock Not Subject to Mandatory Redemption $ 155.6 $ 122.2 $ 116.2 $ 90.4 $ 43.0 $ 31.8 $ — $ — Long-Term Debt 24,413.5 22,855.2 4,814.4 4,572.0 4,496.9 4,273.7 1,431.6 1,292.6 Rate Reduction Bonds 410.5 395.0 — — — — 410.5 395.0

ACCUMULATED OTHER COMPREHENSI_2

ACCUMULATED OTHER COMPREHENSIVE INCOME/(LOSS) (Tables)	3 Months Ended
ACCUMULATED OTHER COMPREHENSIVE INCOME/(LOSS) (Tables)	Mar. 31, 2024
Equity [Abstract]
Changes in Accumulated Other Comprehensive Income/(Loss) by Component, Net of Tax	The changes in accumulated other comprehensive income/(loss) by component, net of tax, are as follows: For the Three Months Ended March 31, 2024 For the Three Months Ended March 31, 2023 Eversource (Millions of Dollars) Qualified Defined Total Qualified Unrealized Defined Total Balance as of Beginning of Period $ (0.4) $ (33.3) $ (33.7) $ (0.4) $ (1.2) $ (37.8) $ (39.4) Amounts Reclassified from AOCI — 5.2 5.2 — 1.2 2.0 3.2 Net OCI — 5.2 5.2 — 1.2 2.0 3.2 Balance as of End of Period $ (0.4) $ (28.1) $ (28.5) $ (0.4) $ — $ (35.8) $ (36.2)

COMMON SHARES (Tables)

COMMON SHARES (Tables)	3 Months Ended
COMMON SHARES (Tables)	Mar. 31, 2024
Equity [Abstract]
Common Shares Authorized and Issued	The following table sets forth the Eversource parent common shares and the shares of common stock of CL&P, NSTAR Electric and PSNH that were authorized and issued, as well as the respective per share par values: Shares Authorized as of March 31, 2024 and December 31, 2023 Issued as of Par Value March 31, 2024 December 31, 2023 Eversource $ 5 410,000,000 361,276,965 359,984,073 CL&P $ 10 24,500,000 6,035,205 6,035,205 NSTAR Electric $ 1 100,000,000 200 200 PSNH $ 1 100,000,000 301 301

EARNINGS PER SHARE (Tables)

EARNINGS PER SHARE (Tables)	3 Months Ended
EARNINGS PER SHARE (Tables)	Mar. 31, 2024
Earnings Per Share [Abstract]
Components of Basic and Diluted EPS	The following table sets forth the components of basic and diluted EPS: Eversource (Millions of Dollars, except share information) For the Three Months Ended March 31, 2024 March 31, 2023 Net Income Attributable to Common Shareholders $ 521.8 $ 491.2 Weighted Average Common Shares Outstanding: Basic 350,717,114 349,217,147 Dilutive Effect 280,106 394,866 Diluted 350,997,220 349,612,013 Basic and Diluted EPS $ 1.49 $ 1.41

REVENUES (Tables)

REVENUES (Tables)	3 Months Ended
REVENUES (Tables)	Mar. 31, 2024
Revenue from Contract with Customer [Abstract]
Operating Revenues Disaggregated by Revenue Source	The following tables present operating revenues disaggregated by revenue source: For the Three Months Ended March 31, 2024 Eversource (Millions of Dollars) Electric Natural Gas Electric Water Distribution Other Eliminations Total Revenues from Contracts with Customers Retail Tariff Sales Residential $ 1,254.1 $ 507.6 $ — $ 30.3 $ — $ — $ 1,792.0 Commercial 707.5 247.1 — 16.2 — (1.7) 969.1 Industrial 87.7 59.8 — 1.0 — (5.1) 143.4 Total Retail Tariff Sales Revenues 2,049.3 814.5 — 47.5 — (6.8) 2,904.5 Wholesale Transmission Revenues — — 474.1 — — (361.6) 112.5 Wholesale Market Sales Revenues 165.3 58.2 — 0.9 — — 224.4 Other Revenues from Contracts with Customers 28.4 1.1 3.9 (0.2) 443.6 (441.4) 35.4 Total Revenues from Contracts with Customers 2,243.0 873.8 478.0 48.2 443.6 (809.8) 3,276.8 Alternative Revenue Programs 13.2 31.5 29.6 1.6 — (26.8) 49.1 Other Revenues 5.5 0.7 0.2 0.3 — — 6.7 Total Operating Revenues $ 2,261.7 $ 906.0 $ 507.8 $ 50.1 $ 443.6 $ (836.6) $ 3,332.6 For the Three Months Ended March 31, 2023 Eversource (Millions of Dollars) Electric Natural Gas Electric Water Distribution Other Eliminations Total Revenues from Contracts with Customers Retail Tariff Sales Residential $ 1,464.0 $ 576.6 $ — $ 28.9 $ — $ — $ 2,069.5 Commercial 788.4 320.0 — 15.5 — (1.0) 1,122.9 Industrial 89.1 69.6 — 1.1 — (5.1) 154.7 Total Retail Tariff Sales Revenues 2,341.5 966.2 — 45.5 — (6.1) 3,347.1 Wholesale Transmission Revenues — — 435.0 — — (325.3) 109.7 Wholesale Market Sales Revenues 217.3 49.1 — 0.8 — — 267.2 Other Revenues from Contracts with Customers 18.3 1.5 4.7 2.1 413.8 (412.6) 27.8 Total Revenues from Contracts with Customers 2,577.1 1,016.8 439.7 48.4 413.8 (744.0) 3,751.8 Alternative Revenue Programs 6.0 27.4 18.7 1.7 — (16.9) 36.9 Other Revenues 5.5 1.0 0.2 0.2 — — 6.9 Total Operating Revenues $ 2,588.6 $ 1,045.2 $ 458.6 $ 50.3 $ 413.8 $ (760.9) $ 3,795.6 For the Three Months Ended March 31, 2024 For the Three Months Ended March 31, 2023 (Millions of Dollars) CL&P NSTAR Electric PSNH CL&P NSTAR Electric PSNH Revenues from Contracts with Customers Retail Tariff Sales Residential $ 626.8 $ 462.2 $ 165.1 $ 762.2 $ 467.8 $ 234.0 Commercial 252.4 373.5 82.0 295.3 384.3 108.6 Industrial 33.3 29.9 24.5 33.9 32.6 22.6 Total Retail Tariff Sales Revenues 912.5 865.6 271.6 1,091.4 884.7 365.2 Wholesale Transmission Revenues 200.7 188.8 84.6 195.8 167.8 71.4 Wholesale Market Sales Revenues 121.2 31.6 12.5 154.6 41.1 21.6 Other Revenues from Contracts with Customers 16.4 11.1 5.2 10.0 10.8 2.9 Total Revenues from Contracts with Customers 1,250.8 1,097.1 373.9 1,451.8 1,104.4 461.1 Alternative Revenue Programs 27.4 7.8 7.6 24.6 (9.5) 9.6 Other Revenues 2.9 2.0 0.8 2.2 2.5 1.0 Eliminations (159.8) (159.3) (56.2) (139.7) (141.1) (51.5) Total Operating Revenues $ 1,121.3 $ 947.6 $ 326.1 $ 1,338.9 $ 956.3 $ 420.2

SEGMENT INFORMATION (Tables)

SEGMENT INFORMATION (Tables)	3 Months Ended
SEGMENT INFORMATION (Tables)	Mar. 31, 2024
Segment Reporting [Abstract]
Summary of Segment Information and Segmented Total Assets	Eversource's segment information is as follows: For the Three Months Ended March 31, 2024 Eversource (Millions of Dollars) Electric Distribution Natural Gas Distribution Electric Transmission Water Distribution Other Eliminations Total Operating Revenues $ 2,261.7 $ 906.0 $ 507.8 $ 50.1 $ 443.6 $ (836.6) $ 3,332.6 Depreciation and Amortization (109.8) (83.0) (101.0) (0.6) (45.7) 2.5 (337.6) Other Operating Expenses (1,905.1) (554.6) (141.9) (32.0) (349.5) 834.1 (2,149.0) Operating Income $ 246.8 $ 268.4 $ 264.9 $ 17.5 $ 48.4 $ — $ 846.0 Interest Expense $ (82.5) $ (24.5) $ (40.9) $ (11.4) $ (146.1) $ 54.7 $ (250.7) Other Income, Net 56.6 10.1 14.1 1.7 622.6 (614.1) 91.0 Net Income Attributable to Common Shareholders 168.1 190.6 176.7 5.4 540.4 (559.4) 521.8 Cash Flows Used for Investments in Plant 471.3 244.8 358.4 31.9 43.0 — 1,149.4 For the Three Months Ended March 31, 2023 Eversource (Millions of Dollars) Electric Natural Gas Electric Water Distribution Other Eliminations Total Operating Revenues $ 2,588.6 $ 1,045.2 $ 458.6 $ 50.3 $ 413.8 $ (760.9) $ 3,795.6 Depreciation and Amortization (22.0) (77.0) (89.9) (13.3) (36.8) 2.1 (236.9) Other Operating Expenses (2,342.3) (730.4) (128.2) (27.9) (339.6) 759.3 (2,809.1) Operating Income $ 224.3 $ 237.8 $ 240.5 $ 9.1 $ 37.4 $ 0.5 $ 749.6 Interest Expense $ (69.3) $ (21.2) $ (41.5) $ (9.4) $ (85.1) $ 32.0 $ (194.5) Other Income, Net 54.3 9.0 9.4 1.1 565.8 (550.6) 89.0 Net Income Attributable to Common Shareholders 165.5 170.3 155.1 1.5 516.9 (518.1) 491.2 Cash Flows Used for Investments in Plant 371.9 165.5 336.6 37.9 65.2 — 977.1 The following table summarizes Eversource's segmented total assets: Eversource (Millions of Dollars) Electric Natural Gas Electric Water Distribution Other Eliminations Total As of March 31, 2024 $ 30,437.0 $ 8,948.5 $ 15,129.8 $ 2,972.2 $ 28,358.1 $ (28,523.4) $ 57,322.2 As of December 31, 2023 29,426.4 8,775.3 14,806.5 2,944.8 26,337.7 (26,678.5) 55,612.2

SUMMARY OF SIGNIFICANT ACCOUN_4

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Narrative (Details) $ in Thousands, customer in Millions			1 Months Ended	3 Months Ended
	Feb. 12, 2024 USD ($)	Sep. 07, 2023 USD ($) a mile	Sep. 30, 2023 USD ($)	Mar. 31, 2024 USD ($) project regulatedUtility customer turbine	Mar. 31, 2023 USD ($)	Jan. 24, 2024	Dec. 31, 2023 USD ($)
Summary of Accounting Policies [Line Items]
Number of electric, natural gas and water customers \| customer				4.4
Number of offshore wind projects \| project				3
Number of tax equity projects \| project				1
Payments for investment				$ 307,433	$ 87,845
Number of turbines \| turbine				6
Percent realized of investment tax credit	0.10
Expected value of investment tax credit	$ 170,000
Energy Relief Fund - Merrimack Valley Programs
Summary of Accounting Policies [Line Items]
Restricted cash, current				$ 20,000			$ 20,000
Restricted cash, noncurrent				$ 13,300			$ 14,100
CL&P
Summary of Accounting Policies [Line Items]
Period of accounts receivable recoverable under financial or medical duress				180 days
Yankee Gas
Summary of Accounting Policies [Line Items]
Period of accounts receivable recoverable under financial or medical duress				90 days
Tax Equity
Summary of Accounting Policies [Line Items]
Ownership interest (percent)				50%
Offshore Wind Business
Summary of Accounting Policies [Line Items]
Ownership interest (percent)				50%
Northeast Offshore LLC And South Fork Class B Member, LLC
Summary of Accounting Policies [Line Items]
Ownership interest (percent)				50%
Number of offshore wind projects \| project				3
South Fork Wind Holdings, LLC Class A shares
Summary of Accounting Policies [Line Items]
Ownership interest (percent)			100%	100%
Expected value of investment tax credit			$ 400,000	$ 193,000
Expected future cash flows of turbines			100,000
Increase (decrease) in taxes payable				(54,000)
Increase (decrease) in deferred tax assets				139,000
Deferred tax assets, tax equity method investments				$ 37,000
Uncommitted Lease Area
Summary of Accounting Policies [Line Items]
Ownership interest (percent)		50%
Uncommitted area of developable acres (in acres) \| a		175,000
Number of miles off south coast of Massachusetts \| mile		25
Payments for investment		$ 625,000
Tax Equity Capital Contribution Agreement
Summary of Accounting Policies [Line Items]
Payments for investment			$ 528,000
Sunrise Wind LLC
Summary of Accounting Policies [Line Items]
Ownership interest (percent)						50%
Sunrise Wind LLC \| Orsted
Summary of Accounting Policies [Line Items]
Equity method investment, percent of purchase price paid at closing (in percent)						0.50
Equity method investment, percent of remaining purchase price paid (in percent)						0.50
South Fork Wind And Revolution Wind
Summary of Accounting Policies [Line Items]
Ownership interest (percent)	50%
Proceeds from sale of equity method investments	$ 1,100,000
Cost sharing agreement, threshold amount	$ 240,000
Renewable Energy Investment Fund
Summary of Accounting Policies [Line Items]
Proceeds from sale of equity method investments					123,400
Renewable Energy Investment Fund \| Equity Method Investee
Summary of Accounting Policies [Line Items]
Charitable contributions					$ 20,000
Orsted
Summary of Accounting Policies [Line Items]
Ownership interest (percent)						50%
Connecticut, Massachusetts and New Hampshire
Summary of Accounting Policies [Line Items]
Number of regulated utilities \| regulatedUtility				12

SUMMARY OF SIGNIFICANT ACCOUN_5

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Provision for Uncollectible Accounts (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Balance	$ 554,500	$ 486,300
Uncollectible Expense	16,387	22,821
Uncollectible Costs Deferred	38,900	58,000
Write-Offs	(43,600)	(36,000)
Recoveries Collected	3,900	4,000
Ending Balance	570,100	535,100
CL&P
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Balance	296,000	225,300
Uncollectible Expense	3,507	3,876
Uncollectible Costs Deferred	25,400	37,000
Write-Offs	(18,500)	(14,300)
Recoveries Collected	1,400	1,500
Ending Balance	307,800	253,400
NSTAR Electric
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Balance	97,000	95,000
Uncollectible Expense	6,109	4,697
Uncollectible Costs Deferred	3,600	4,100
Write-Offs	(10,200)	(10,700)
Recoveries Collected	1,200	1,500
Ending Balance	97,700	94,600
PSNH
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Balance	14,300	29,200
Uncollectible Expense	1,163	5,060
Uncollectible Costs Deferred	1,300	1,200
Write-Offs	(3,200)	(2,200)
Recoveries Collected	200	200
Ending Balance	13,800	33,500
Hardship Accounts
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Balance	366,800	284,400
Uncollectible Expense	0	0
Uncollectible Costs Deferred	27,500	43,700
Write-Offs	(15,100)	(9,700)
Recoveries Collected	200	300
Ending Balance	379,400	318,700
Hardship Accounts \| CL&P
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Balance	259,700	188,900
Uncollectible Expense	0	0
Uncollectible Costs Deferred	22,700	34,300
Write-Offs	(10,800)	(7,300)
Recoveries Collected	200	300
Ending Balance	271,800	216,200
Hardship Accounts \| NSTAR Electric
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Balance	43,600	43,700
Uncollectible Expense	0	0
Uncollectible Costs Deferred	(800)	(1,300)
Write-Offs	(1,000)	(400)
Recoveries Collected	0	0
Ending Balance	41,800	42,000
Retail (Non-Hardship), Wholesale, and Other
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Balance	187,700	201,900
Uncollectible Expense	16,400	22,800
Uncollectible Costs Deferred	11,400	14,300
Write-Offs	(28,500)	(26,300)
Recoveries Collected	3,700	3,700
Ending Balance	190,700	216,400
Retail (Non-Hardship), Wholesale, and Other \| CL&P
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Balance	36,300	36,400
Uncollectible Expense	3,500	3,900
Uncollectible Costs Deferred	2,700	2,700
Write-Offs	(7,700)	(7,000)
Recoveries Collected	1,200	1,200
Ending Balance	36,000	37,200
Retail (Non-Hardship), Wholesale, and Other \| NSTAR Electric
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Balance	53,400	51,300
Uncollectible Expense	6,100	4,700
Uncollectible Costs Deferred	4,400	5,400
Write-Offs	(9,200)	(10,300)
Recoveries Collected	1,200	1,500
Ending Balance	$ 55,900	$ 52,600

SUMMARY OF SIGNIFICANT ACCOUN_6

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Components of Other Income, Net (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Summary of Accounting Policies [Line Items]
Other income, net	$ 91,030	$ 88,981
Pension, SERP and PBOP Non-Service Income Components, Net of Deferred Portion
Summary of Accounting Policies [Line Items]
Other income, net	27,800	34,800
AFUDC Equity
Summary of Accounting Policies [Line Items]
Other income, net	26,800	15,500
Equity in Earnings of Unconsolidated Affiliates
Summary of Accounting Policies [Line Items]
Other income, net	7,800	3,800
Investment (Loss)/Income
Summary of Accounting Policies [Line Items]
Other income, net	(800)	(1,700)
Interest Income
Summary of Accounting Policies [Line Items]
Other income, net	30,000	23,100
Other
Summary of Accounting Policies [Line Items]
Other income, net	(600)	13,500
CL&P
Summary of Accounting Policies [Line Items]
Other income, net	16,468	14,937
CL&P \| Pension, SERP and PBOP Non-Service Income Components, Net of Deferred Portion
Summary of Accounting Policies [Line Items]
Other income, net	6,500	9,500
CL&P \| AFUDC Equity
Summary of Accounting Policies [Line Items]
Other income, net	6,000	4,100
CL&P \| Equity in Earnings of Unconsolidated Affiliates
Summary of Accounting Policies [Line Items]
Other income, net	0	0
CL&P \| Investment (Loss)/Income
Summary of Accounting Policies [Line Items]
Other income, net	(700)	(600)
CL&P \| Interest Income
Summary of Accounting Policies [Line Items]
Other income, net	4,700	1,900
CL&P \| Other
Summary of Accounting Policies [Line Items]
Other income, net	0	0
NSTAR Electric
Summary of Accounting Policies [Line Items]
Other income, net	47,114	39,873
NSTAR Electric \| Pension, SERP and PBOP Non-Service Income Components, Net of Deferred Portion
Summary of Accounting Policies [Line Items]
Other income, net	12,300	14,700
NSTAR Electric \| AFUDC Equity
Summary of Accounting Policies [Line Items]
Other income, net	16,200	9,500
NSTAR Electric \| Equity in Earnings of Unconsolidated Affiliates
Summary of Accounting Policies [Line Items]
Other income, net	200	100
NSTAR Electric \| Investment (Loss)/Income
Summary of Accounting Policies [Line Items]
Other income, net	400	(500)
NSTAR Electric \| Interest Income
Summary of Accounting Policies [Line Items]
Other income, net	18,000	16,000
NSTAR Electric \| Other
Summary of Accounting Policies [Line Items]
Other income, net	0	100
PSNH
Summary of Accounting Policies [Line Items]
Other income, net	7,050	5,717
PSNH \| Pension, SERP and PBOP Non-Service Income Components, Net of Deferred Portion
Summary of Accounting Policies [Line Items]
Other income, net	3,600	4,200
PSNH \| AFUDC Equity
Summary of Accounting Policies [Line Items]
Other income, net	1,900	700
PSNH \| Equity in Earnings of Unconsolidated Affiliates
Summary of Accounting Policies [Line Items]
Other income, net	0	0
PSNH \| Investment (Loss)/Income
Summary of Accounting Policies [Line Items]
Other income, net	(200)	(100)
PSNH \| Interest Income
Summary of Accounting Policies [Line Items]
Other income, net	1,800	900
PSNH \| Other
Summary of Accounting Policies [Line Items]
Other income, net	$ 0	$ 0

SUMMARY OF SIGNIFICANT ACCOUN_7

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Investments in Unconsolidated Affiliates (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Schedule of Equity Method Investments [Line Items]
Investments in unconsolidated affiliates	$ 741,697	$ 660,473
Offshore Wind Business
Schedule of Equity Method Investments [Line Items]
Ownership interest (percent)	50%
Investments in unconsolidated affiliates	$ 596,400	515,500
Offshore Wind Business \| Maximum
Schedule of Equity Method Investments [Line Items]
Ownership interest (percent)	100%
Offshore Wind Business \| Minimum
Schedule of Equity Method Investments [Line Items]
Ownership interest (percent)	50%
Natural Gas Pipeline - Algonquin Gas Transmission, LLC
Schedule of Equity Method Investments [Line Items]
Ownership interest (percent)	15%
Investments in unconsolidated affiliates	$ 115,900	116,000
Other
Schedule of Equity Method Investments [Line Items]
Investments in unconsolidated affiliates	$ 29,400	$ 29,000

SUMMARY OF SIGNIFICANT ACCOUN_8

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Other Taxes (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Schedule of Gross Tax Receipts [Line Items]
Gross receipts taxes	$ 53.3	$ 55
CL&P
Schedule of Gross Tax Receipts [Line Items]
Gross receipts taxes	$ 43.9	$ 43.1

SUMMARY OF SIGNIFICANT ACCOUN_9

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Non-cash Investing Activities (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Schedule of Supplemental Cash Flow [Line Items]
Plant additions included in accounts payable	$ 453.6	$ 400.8
CL&P
Schedule of Supplemental Cash Flow [Line Items]
Plant additions included in accounts payable	112.8	101.9
NSTAR Electric
Schedule of Supplemental Cash Flow [Line Items]
Plant additions included in accounts payable	132.7	117.4
PSNH
Schedule of Supplemental Cash Flow [Line Items]
Plant additions included in accounts payable	$ 75.2	$ 54.6

SUMMARY OF SIGNIFICANT ACCOU_10

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Reconciliation of Cash Balances to Cash and Restricted Cash (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023	Mar. 31, 2023	Dec. 31, 2022
Restricted Cash and Cash Equivalents Items [Line Items]
Cash as reported on the Balance Sheets	$ 259,213	$ 53,873
Cash and Restricted Cash as reported on the Statements of Cash Flows	360,396	166,418	$ 162,767	$ 521,752
Special Deposits
Restricted Cash and Cash Equivalents Items [Line Items]
Restricted cash	68,700	81,500
Marketable Securities
Restricted Cash and Cash Equivalents Items [Line Items]
Restricted cash	16,000	13,700
Other Long-Term Assets
Restricted Cash and Cash Equivalents Items [Line Items]
Restricted cash	16,500	17,300
CL&P
Restricted Cash and Cash Equivalents Items [Line Items]
Cash as reported on the Balance Sheets	29,006	10,213
Cash and Restricted Cash as reported on the Statements of Cash Flows	31,055	12,243	18,409	20,327
CL&P \| Special Deposits
Restricted Cash and Cash Equivalents Items [Line Items]
Restricted cash	2,100	2,000
CL&P \| Marketable Securities
Restricted Cash and Cash Equivalents Items [Line Items]
Restricted cash	0	0
CL&P \| Other Long-Term Assets
Restricted Cash and Cash Equivalents Items [Line Items]
Restricted cash	0	0
NSTAR Electric
Restricted Cash and Cash Equivalents Items [Line Items]
Cash as reported on the Balance Sheets	20,226	6,740
Cash and Restricted Cash as reported on the Statements of Cash Flows	36,503	22,785	18,355	345,293
NSTAR Electric \| Special Deposits
Restricted Cash and Cash Equivalents Items [Line Items]
Restricted cash	16,300	16,100
NSTAR Electric \| Marketable Securities
Restricted Cash and Cash Equivalents Items [Line Items]
Restricted cash	0	0
NSTAR Electric \| Other Long-Term Assets
Restricted Cash and Cash Equivalents Items [Line Items]
Restricted cash	0	0
PSNH
Restricted Cash and Cash Equivalents Items [Line Items]
Cash as reported on the Balance Sheets	14,067	240
Cash and Restricted Cash as reported on the Statements of Cash Flows	34,311	35,004	$ 23,012	$ 36,812
PSNH \| Special Deposits
Restricted Cash and Cash Equivalents Items [Line Items]
Restricted cash	17,000	31,600
PSNH \| Marketable Securities
Restricted Cash and Cash Equivalents Items [Line Items]
Restricted cash	0	0
PSNH \| Other Long-Term Assets
Restricted Cash and Cash Equivalents Items [Line Items]
Restricted cash	$ 3,200	$ 3,200

REGULATORY ACCOUNTING - Compone

REGULATORY ACCOUNTING - Components of Regulatory Assets (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Regulatory Assets [Line Items]
Total Regulatory Assets	$ 6,728,800	$ 6,389,200
Less: Current Portion	1,889,499	1,674,196
Total Long-Term Regulatory Assets	4,839,271	4,714,970
Storm Costs, Net
Regulatory Assets [Line Items]
Total Regulatory Assets	1,942,700	1,785,900
Regulatory Tracking Mechanisms
Regulatory Assets [Line Items]
Total Regulatory Assets	1,541,200	1,319,200
Benefit Costs
Regulatory Assets [Line Items]
Total Regulatory Assets	1,098,100	1,117,300
Income Taxes, Net
Regulatory Assets [Line Items]
Total Regulatory Assets	925,700	912,400
Securitized Stranded Costs
Regulatory Assets [Line Items]
Total Regulatory Assets	381,700	392,500
Goodwill-related
Regulatory Assets [Line Items]
Total Regulatory Assets	259,900	264,100
Asset Retirement Obligations
Regulatory Assets [Line Items]
Total Regulatory Assets	141,000	137,900
Derivative Liabilities
Regulatory Assets [Line Items]
Total Regulatory Assets	103,700	120,900
Other Regulatory Assets
Regulatory Assets [Line Items]
Total Regulatory Assets	334,800	339,000
CL&P
Regulatory Assets [Line Items]
Total Regulatory Assets	2,427,700	2,143,200
Less: Current Portion	717,608	480,369
Total Long-Term Regulatory Assets	1,710,091	1,662,778
CL&P \| Storm Costs, Net
Regulatory Assets [Line Items]
Total Regulatory Assets	957,600	896,600
CL&P \| Regulatory Tracking Mechanisms
Regulatory Assets [Line Items]
Total Regulatory Assets	593,500	354,500
CL&P \| Benefit Costs
Regulatory Assets [Line Items]
Total Regulatory Assets	194,500	197,400
CL&P \| Income Taxes, Net
Regulatory Assets [Line Items]
Total Regulatory Assets	517,500	512,600
CL&P \| Securitized Stranded Costs
Regulatory Assets [Line Items]
Total Regulatory Assets	0	0
CL&P \| Goodwill-related
Regulatory Assets [Line Items]
Total Regulatory Assets	0	0
CL&P \| Asset Retirement Obligations
Regulatory Assets [Line Items]
Total Regulatory Assets	39,100	38,500
CL&P \| Derivative Liabilities
Regulatory Assets [Line Items]
Total Regulatory Assets	103,700	120,900
CL&P \| Other Regulatory Assets
Regulatory Assets [Line Items]
Total Regulatory Assets	21,800	22,700
NSTAR Electric
Regulatory Assets [Line Items]
Total Regulatory Assets	2,040,900	1,957,900
Less: Current Portion	718,726	676,083
Total Long-Term Regulatory Assets	1,322,249	1,281,836
NSTAR Electric \| Storm Costs, Net
Regulatory Assets [Line Items]
Total Regulatory Assets	657,300	609,100
NSTAR Electric \| Regulatory Tracking Mechanisms
Regulatory Assets [Line Items]
Total Regulatory Assets	522,300	482,900
NSTAR Electric \| Benefit Costs
Regulatory Assets [Line Items]
Total Regulatory Assets	330,200	336,700
NSTAR Electric \| Income Taxes, Net
Regulatory Assets [Line Items]
Total Regulatory Assets	133,600	128,600
NSTAR Electric \| Securitized Stranded Costs
Regulatory Assets [Line Items]
Total Regulatory Assets	0	0
NSTAR Electric \| Goodwill-related
Regulatory Assets [Line Items]
Total Regulatory Assets	223,100	226,700
NSTAR Electric \| Asset Retirement Obligations
Regulatory Assets [Line Items]
Total Regulatory Assets	73,800	72,300
NSTAR Electric \| Derivative Liabilities
Regulatory Assets [Line Items]
Total Regulatory Assets	0	0
NSTAR Electric \| Other Regulatory Assets
Regulatory Assets [Line Items]
Total Regulatory Assets	100,600	101,600
PSNH
Regulatory Assets [Line Items]
Total Regulatory Assets	999,600	963,300
Less: Current Portion	188,057	189,450
Total Long-Term Regulatory Assets	811,457	773,783
PSNH \| Storm Costs, Net
Regulatory Assets [Line Items]
Total Regulatory Assets	327,800	280,200
PSNH \| Regulatory Tracking Mechanisms
Regulatory Assets [Line Items]
Total Regulatory Assets	184,900	182,200
PSNH \| Benefit Costs
Regulatory Assets [Line Items]
Total Regulatory Assets	78,000	79,300
PSNH \| Income Taxes, Net
Regulatory Assets [Line Items]
Total Regulatory Assets	15,500	16,400
PSNH \| Securitized Stranded Costs
Regulatory Assets [Line Items]
Total Regulatory Assets	381,700	392,500
PSNH \| Goodwill-related
Regulatory Assets [Line Items]
Total Regulatory Assets	0	0
PSNH \| Asset Retirement Obligations
Regulatory Assets [Line Items]
Total Regulatory Assets	4,900	4,700
PSNH \| Derivative Liabilities
Regulatory Assets [Line Items]
Total Regulatory Assets	0	0
PSNH \| Other Regulatory Assets
Regulatory Assets [Line Items]
Total Regulatory Assets	$ 6,800	$ 8,000

REGULATORY ACCOUNTING - Narrati

REGULATORY ACCOUNTING - Narrative (Details) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Regulatory Assets [Line Items]
Amount of regulatory costs not yet approved	$ 243.9	$ 241.7
Regulatory costs	75.9	82.1
Regulatory assets	6,728.8	6,389.2
CL&P
Regulatory Assets [Line Items]
Amount of regulatory costs not yet approved	169.2	166.7
Regulatory costs	60.7	64
Regulatory assets	2,427.7	2,143.2
NSTAR Electric
Regulatory Assets [Line Items]
Amount of regulatory costs not yet approved	21.7	21.9
Regulatory costs	6.5	7.3
Regulatory assets	2,040.9	1,957.9
PSNH
Regulatory Assets [Line Items]
Amount of regulatory costs not yet approved	1.3	1.2
Regulatory assets	$ 999.6	$ 963.3

REGULATORY ACCOUNTING - Compo_2

REGULATORY ACCOUNTING - Components of Regulatory Liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Regulatory Liabilities [Line Items]
Total Regulatory Liabilities	$ 4,692,900	$ 4,614,700
Less: Current Portion	641,472	591,750
Total Long-Term Regulatory Liabilities	4,051,377	4,022,923
EDIT due to Tax Cuts and Jobs Act of 2017
Regulatory Liabilities [Line Items]
Total Regulatory Liabilities	2,537,000	2,548,600
Regulatory Tracking Mechanisms
Regulatory Liabilities [Line Items]
Total Regulatory Liabilities	711,700	668,300
Cost of Removal
Regulatory Liabilities [Line Items]
Total Regulatory Liabilities	687,600	666,600
Deferred Portion of Non-Service Income Components of Pension, SERP and PBOP
Regulatory Liabilities [Line Items]
Total Regulatory Liabilities	373,200	354,000
AFUDC - Transmission
Regulatory Liabilities [Line Items]
Total Regulatory Liabilities	135,500	124,300
Benefit Costs
Regulatory Liabilities [Line Items]
Total Regulatory Liabilities	44,800	51,000
Other Regulatory Liabilities
Regulatory Liabilities [Line Items]
Total Regulatory Liabilities	203,100	201,900
CL&P
Regulatory Liabilities [Line Items]
Total Regulatory Liabilities	1,451,200	1,418,100
Less: Current Portion	117,335	102,239
Total Long-Term Regulatory Liabilities	1,333,875	1,315,928
CL&P \| EDIT due to Tax Cuts and Jobs Act of 2017
Regulatory Liabilities [Line Items]
Total Regulatory Liabilities	966,100	969,200
CL&P \| Regulatory Tracking Mechanisms
Regulatory Liabilities [Line Items]
Total Regulatory Liabilities	167,500	154,000
CL&P \| Cost of Removal
Regulatory Liabilities [Line Items]
Total Regulatory Liabilities	168,200	157,900
CL&P \| Deferred Portion of Non-Service Income Components of Pension, SERP and PBOP
Regulatory Liabilities [Line Items]
Total Regulatory Liabilities	53,100	49,900
CL&P \| AFUDC - Transmission
Regulatory Liabilities [Line Items]
Total Regulatory Liabilities	58,500	56,100
CL&P \| Benefit Costs
Regulatory Liabilities [Line Items]
Total Regulatory Liabilities	500	600
CL&P \| Other Regulatory Liabilities
Regulatory Liabilities [Line Items]
Total Regulatory Liabilities	37,300	30,400
NSTAR Electric
Regulatory Liabilities [Line Items]
Total Regulatory Liabilities	2,008,300	1,953,400
Less: Current Portion	405,190	368,070
Total Long-Term Regulatory Liabilities	1,603,079	1,585,311
NSTAR Electric \| EDIT due to Tax Cuts and Jobs Act of 2017
Regulatory Liabilities [Line Items]
Total Regulatory Liabilities	899,500	905,100
NSTAR Electric \| Regulatory Tracking Mechanisms
Regulatory Liabilities [Line Items]
Total Regulatory Liabilities	384,200	347,200
NSTAR Electric \| Cost of Removal
Regulatory Liabilities [Line Items]
Total Regulatory Liabilities	431,000	420,900
NSTAR Electric \| Deferred Portion of Non-Service Income Components of Pension, SERP and PBOP
Regulatory Liabilities [Line Items]
Total Regulatory Liabilities	184,900	175,900
NSTAR Electric \| AFUDC - Transmission
Regulatory Liabilities [Line Items]
Total Regulatory Liabilities	77,000	68,200
NSTAR Electric \| Benefit Costs
Regulatory Liabilities [Line Items]
Total Regulatory Liabilities	18,000	22,200
NSTAR Electric \| Other Regulatory Liabilities
Regulatory Liabilities [Line Items]
Total Regulatory Liabilities	13,700	13,900
PSNH
Regulatory Liabilities [Line Items]
Total Regulatory Liabilities	475,500	511,100
Less: Current Portion	86,141	117,515
Total Long-Term Regulatory Liabilities	389,427	393,574
PSNH \| EDIT due to Tax Cuts and Jobs Act of 2017
Regulatory Liabilities [Line Items]
Total Regulatory Liabilities	337,500	339,300
PSNH \| Regulatory Tracking Mechanisms
Regulatory Liabilities [Line Items]
Total Regulatory Liabilities	80,200	114,400
PSNH \| Cost of Removal
Regulatory Liabilities [Line Items]
Total Regulatory Liabilities	14,800	16,200
PSNH \| Deferred Portion of Non-Service Income Components of Pension, SERP and PBOP
Regulatory Liabilities [Line Items]
Total Regulatory Liabilities	38,200	36,600
PSNH \| AFUDC - Transmission
Regulatory Liabilities [Line Items]
Total Regulatory Liabilities	0	0
PSNH \| Benefit Costs
Regulatory Liabilities [Line Items]
Total Regulatory Liabilities	0	0
PSNH \| Other Regulatory Liabilities
Regulatory Liabilities [Line Items]
Total Regulatory Liabilities	$ 4,800	$ 4,600

PROPERTY, PLANT AND EQUIPMENT_3

PROPERTY, PLANT AND EQUIPMENT AND ACCUMULATED DEPRECIATION - Summary of Property, Plant, and Equipment (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Public Utility, Property, Plant and Equipment [Line Items]
Distribution - Electric	$ 19,929,500	$ 19,656,500
Distribution - Natural Gas	8,234,700	8,155,300
Transmission - Electric	15,182,600	14,666,800
Distribution - Water	2,294,900	2,280,100
Solar	201,100	201,100
Utility	45,842,800	44,959,800
Other	2,069,300	2,006,800
Property, Plant and Equipment, Gross	47,912,100	46,966,600
Less: Accumulated Depreciation
Utility	(9,835,700)	(9,670,100)
Other	(916,200)	(869,600)
Total Accumulated Depreciation	(10,751,900)	(10,539,700)
Property, Plant and Equipment, Net	37,160,200	36,426,900
Construction Work in Progress	3,129,200	3,071,700
Total Property, Plant and Equipment, Net	40,289,378	39,498,607
CL&P
Public Utility, Property, Plant and Equipment [Line Items]
Distribution - Electric	8,003,900	7,897,100
Transmission - Electric	6,609,200	6,548,200
Solar	0	0
Property, Plant and Equipment, Gross	14,613,100	14,445,300
Less: Accumulated Depreciation
Total Accumulated Depreciation	(2,707,900)	(2,670,500)
Property, Plant and Equipment, Net	11,905,200	11,774,800
Construction Work in Progress	627,300	565,400
Total Property, Plant and Equipment, Net	12,532,477	12,340,192
NSTAR Electric
Public Utility, Property, Plant and Equipment [Line Items]
Distribution - Electric	9,138,500	9,000,500
Transmission - Electric	6,014,500	5,630,800
Solar	201,100	201,100
Property, Plant and Equipment, Gross	15,354,100	14,832,400
Less: Accumulated Depreciation
Total Accumulated Depreciation	(3,648,700)	(3,585,900)
Property, Plant and Equipment, Net	11,705,400	11,246,500
Construction Work in Progress	1,334,900	1,507,300
Total Property, Plant and Equipment, Net	13,040,321	12,753,787
PSNH
Public Utility, Property, Plant and Equipment [Line Items]
Distribution - Electric	2,827,400	2,799,200
Transmission - Electric	2,560,500	2,489,500
Solar	0	0
Property, Plant and Equipment, Gross	5,387,900	5,288,700
Less: Accumulated Depreciation
Total Accumulated Depreciation	(1,004,700)	(984,000)
Property, Plant and Equipment, Net	4,383,200	4,304,700
Construction Work in Progress	324,400	270,000
Total Property, Plant and Equipment, Net	$ 4,707,625	$ 4,574,652

DERIVATIVE INSTRUMENTS - Gross

DERIVATIVE INSTRUMENTS - Gross Fair Values and Net Amounts of Contracts (Details) - CL&P - Level 2 - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Current Derivative Assets
Derivative Assets (Liabilities), at Fair Value, Net, by Balance Sheet Classification [Abstract]
Commodity Supply and Price Risk Management	$ 15.8	$ 16.4
Netting	(0.4)	(0.5)
Net Amount Recorded as a Derivative	15.4	15.9
Long-Term Derivative Assets
Derivative Assets (Liabilities), at Fair Value, Net, by Balance Sheet Classification [Abstract]
Commodity Supply and Price Risk Management	9.9	13.6
Netting	(0.4)	(0.5)
Net Amount Recorded as a Derivative	9.5	13.1
Current Derivative Liabilities
Current and Long-Term Derivative Liabilities
Commodity Supply and Price Risk Management	(79.2)	(81.9)
Netting	0	0
Net Amount Recorded as a Derivative	(79.2)	(81.9)
Long-Term Derivative Liabilities
Current and Long-Term Derivative Liabilities
Commodity Supply and Price Risk Management	(49.4)	(68)
Netting	0	0
Net Amount Recorded as a Derivative	$ (49.4)	$ (68)

DERIVATIVE INSTRUMENTS - Narrat

DERIVATIVE INSTRUMENTS - Narrative (Details) $ in Millions	3 Months Ended
DERIVATIVE INSTRUMENTS - Narrative (Details) $ in Millions	Mar. 31, 2024 USD ($) MW	Mar. 31, 2023 USD ($)	Dec. 31, 2023 MW
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Percentage of costs or benefits borne under capacity-related contracts by United Illuminated Company (in percent)	20%
Amount of power to be purchased under capacity-related contract (in MW) \| MW	682		682
CL&P
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Percentage of costs or benefits borne under capacity-related contracts (in percent)	80%
Derivative instruments gain (loss) recognized in regulatory asset liability \| $	$ (1)	$ (1.9)

DERIVATIVE INSTRUMENTS - Change

DERIVATIVE INSTRUMENTS - Changes in the Level 3 Category of Derivative Assets Measured at Fair Value on a Recurring Basis (Details) - CL&P - Level 2 $ in Millions	3 Months Ended
	Mar. 31, 2023 USD ($)
Derivatives, Net [Rollforward]
Fair Value as of Beginning of Period	$ (181.8)
Net Realized/Unrealized Losses Included in Regulatory Assets	(1.9)
Settlements	14.9
Fair Value as of End of Period	$ (168.8)

MARKETABLE SECURITIES - Narrati

MARKETABLE SECURITIES - Narrative (Details) - USD ($)	3 Months Ended
MARKETABLE SECURITIES - Narrative (Details) - USD ($)	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023	Dec. 31, 2022
Debt Securities, Available-for-sale [Line Items]
Available-for-sale equity securities	$ 3,700,000		$ 3,300,000
Unrealized (loss) gain recorded in other income	400,000	$ 800,000
Credit loss	0	0
Allowance for credit loss	0
Allowance for uncollectible accounts for late fees and other receivable amounts	570,100,000	$ 535,100,000	554,500,000	$ 486,300,000
CYAPC and YAEC
Debt Securities, Available-for-sale [Line Items]
Available-for-sale equity securities	172,300,000		173,600,000
Marketable securities held in nuclear decommissioning trust	$ 162,000,000		$ 164,300,000

MARKETABLE SECURITIES - Summary

MARKETABLE SECURITIES - Summary of Available-for-Sale Debt Securities (Details) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Investments, Debt and Equity Securities [Abstract]
Amortized Cost	$ 170.5	$ 169.5
Pre-Tax Unrealized Gains	0.2	1.4
Pre-Tax Unrealized Losses	(8.7)	(6.6)
Fair Value	$ 162	$ 164.3

MARKETABLE SECURITIES - Contrac

MARKETABLE SECURITIES - Contractual Maturities of Available-for-Sale Debt Securities (Details) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Amortized Cost
Less than one year	$ 19.4
One to five years	31.5
Six to ten years	37.7
Greater than ten years	81.9
Amortized Cost	170.5	$ 169.5
Fair Value
Less than one year	19.4
One to five years	31
Six to ten years	36.4
Greater than ten years	75.2
Fair Value	$ 162	$ 164.3

MARKETABLE SECURITIES - Marketa

MARKETABLE SECURITIES - Marketable Securities Recorded at Fair Value on a Recurring Basis by Level (Details) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	$ 338	$ 341.2
Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	192	190.6
Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	146	150.6
Mutual Funds and Equities \| Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	176	176.9
Money Market Funds \| Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	16	13.7
U.S. Government Issued Debt Securities (Agency and Treasury) \| Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	89.2	90.1
Corporate Debt Securities \| Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	34.2	34
Asset-Backed Debt Securities \| Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	5.4	5.6
Municipal Bonds \| Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	7.3	9.8
Other Fixed Income Securities \| Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities	$ 9.9	$ 11.1

SHORT-TERM AND LONG-TERM DEBT -

SHORT-TERM AND LONG-TERM DEBT - Narrative (Details)	1 Months Ended	3 Months Ended
SHORT-TERM AND LONG-TERM DEBT - Narrative (Details)	Jun. 30, 2024 USD ($)	Mar. 31, 2024 USD ($) bond	May 01, 2024 USD ($)	Feb. 08, 2024 USD ($)	Dec. 31, 2023 USD ($)
Line of Credit Facility [Line Items]
Long-Term Debt		$ 24,929,813,000			$ 23,588,616,000
Long-term debt, current maturities classified as noncurrent		1,390,000,000
NSTAR Electric
Line of Credit Facility [Line Items]
Long-Term Debt		4,497,954,000			4,496,947,000
CL&P
Line of Credit Facility [Line Items]
Long-Term Debt		4,814,040,000			4,814,429,000
Notes payable to Eversource parent		426,100,000			249,670,000
CL&P \| Related Party
Line of Credit Facility [Line Items]
Long-Term Debt					207,300,000
Notes payable to Eversource parent		426,100,000			457,000,000
PSNH
Line of Credit Facility [Line Items]
Long-Term Debt		1,682,679,000			1,431,591,000
Notes payable to Eversource parent		0			233,000,000
PSNH \| Related Party
Line of Credit Facility [Line Items]
Long-Term Debt		251,000,000
Notes payable to Eversource parent		$ 251,000,000			233,000,000
NSTAR Gas \| First Mortgage
Line of Credit Facility [Line Items]
Number of first mortgage bonds closed \| bond		2
NSTAR Gas \| First Mortgage \| NSTAR Gas, First Mortgage Bonds, Series W \| Forecast
Line of Credit Facility [Line Items]
Issuances	$ 160,000,000
NSTAR Gas \| First Mortgage \| NSTAR Gas, First Mortgage Bonds, Series X \| Forecast
Line of Credit Facility [Line Items]
Issuances	$ 40,000,000
Line of Credit \| NSTAR Electric \| Subsequent Event
Line of Credit Facility [Line Items]
Maximum borrowing capacity			$ 2,400,000,000
Line of Credit \| CL&P
Line of Credit Facility [Line Items]
Maximum borrowing capacity		$ 375,000,000
Amount outstanding under line of credit		0
Line of Credit \| PSNH
Line of Credit Facility [Line Items]
Maximum borrowing capacity		250,000,000		$ 300,000,000
Amount outstanding under line of credit		0
Commercial Paper \| NSTAR Electric
Line of Credit Facility [Line Items]
Maximum borrowing capacity		650,000,000
Commercial Paper \| CL&P
Line of Credit Facility [Line Items]
Long-Term Debt					207,300,000
Commercial Paper \| PSNH
Line of Credit Facility [Line Items]
Long-Term Debt		251,000,000
Line of Credit
Line of Credit Facility [Line Items]
Amount outstanding under line of credit		0			$ 0
Line of Credit \| NSTAR Electric
Line of Credit Facility [Line Items]
Maximum borrowing capacity		650,000,000
Eversource Parent \| Commercial Paper
Line of Credit Facility [Line Items]
Maximum borrowing capacity		2,000,000,000
Eversource Parent \| Line of Credit
Line of Credit Facility [Line Items]
Maximum borrowing capacity		$ 2,000,000,000
Debt instrument term (in years)		5 years
NSTAR Electric \| Line of Credit \| NSTAR Electric
Line of Credit Facility [Line Items]
Debt instrument term (in years)		5 years

SHORT-TERM AND LONG-TERM DEBT_2

SHORT-TERM AND LONG-TERM DEBT - Borrowings Outstanding and Available under the Commercial Paper Programs (Details) - Commercial Paper - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Debt Instrument [Line Items]
Borrowings outstanding	$ 1,934.9	$ 1,771.9
Available borrowing capacity	$ 65.1	$ 228.1
Weighted-average interest rate (in percent)	5.66%	5.60%
NSTAR Electric
Debt Instrument [Line Items]
Borrowings outstanding	$ 419	$ 365.8
Available borrowing capacity	$ 231	$ 284.2
Weighted-average interest rate (in percent)	5.38%	5.40%

SHORT-TERM AND LONG-TERM DEBT_3

SHORT-TERM AND LONG-TERM DEBT - Summary of Long-Term Debt Issuance and Repayments (Details) - USD ($) $ in Millions	1 Months Ended
	Apr. 30, 2024	Jan. 31, 2024
Senior Notes \| Eversource Parent Series DD Senior Notes \| Eversource Parent
Debt Instrument [Line Items]
Interest rate, stated percentage (in percent)		5%
Issuances		$ 350
Senior Notes \| Eversource Parent Series EE Senior Notes \| Eversource Parent
Debt Instrument [Line Items]
Interest rate, stated percentage (in percent)		5.50%
Issuances		$ 650
Senior Notes \| Eversource Parent Series FF Senior Notes \| Subsequent Event \| Eversource Parent
Debt Instrument [Line Items]
Interest rate, stated percentage (in percent)	5.85%
Issuances	$ 700
Senior Notes \| Eversource Parent Series GG Senior Notes \| Subsequent Event \| Eversource Parent
Debt Instrument [Line Items]
Interest rate, stated percentage (in percent)	5.95%
Issuances	$ 700
CL&P \| First Mortgage \| CL&P 2024 Series A First Mortgage Bonds
Debt Instrument [Line Items]
Interest rate, stated percentage (in percent)		4.65%
Issuances		$ 350
PSNH \| First Mortgage \| PSNH Series X First Mortgage Bonds \| Subsequent Event
Debt Instrument [Line Items]
Interest rate, stated percentage (in percent)	5.35%
Issuances	$ 300

RATE REDUCTION BONDS AND VARI_3

RATE REDUCTION BONDS AND VARIABLE INTEREST ENTITIES - Narrative (Details) - PSNH - Rate Reduction Bonds $ in Millions	May 31, 2018 USD ($)
Debt Instrument [Line Items]
Amount of securitized rate reduction bonds issued	$ 635.7
Weighted average interest rate (in percent)	3.66%

RATE REDUCTION BONDS AND VARI_4

RATE REDUCTION BONDS AND VARIABLE INTEREST ENTITIES - Summary of the Impact of Funding on the Balance Sheets (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Condensed Balance Sheet Statements, Captions [Line Items]
Securitized Stranded Cost (included in Regulatory Assets)	$ 6,728,800	$ 6,389,200
Regulatory Liabilities	4,051,377	4,022,923
Accrued Interest (included in Other Current Liabilities)	1,050,998	1,081,981
Rate Reduction Bonds - Current Portion	43,210	43,210
Rate Reduction Bonds - Long-Term Portion	345,677	367,282
Securitized Stranded Costs
Condensed Balance Sheet Statements, Captions [Line Items]
Securitized Stranded Cost (included in Regulatory Assets)	381,700	392,500
Other Regulatory Assets
Condensed Balance Sheet Statements, Captions [Line Items]
Securitized Stranded Cost (included in Regulatory Assets)	334,800	339,000
Current Derivative Assets
Condensed Balance Sheet Statements, Captions [Line Items]
Restricted Cash	68,700	81,500
Other Long-Term Assets
Condensed Balance Sheet Statements, Captions [Line Items]
Restricted Cash	16,500	17,300
PSNH
Condensed Balance Sheet Statements, Captions [Line Items]
Securitized Stranded Cost (included in Regulatory Assets)	999,600	963,300
Regulatory Liabilities	389,427	393,574
Accrued Interest (included in Other Current Liabilities)	63,096	72,328
Rate Reduction Bonds - Current Portion	43,210	43,210
Rate Reduction Bonds - Long-Term Portion	345,677	367,282
PSNH \| VIE
Condensed Balance Sheet Statements, Captions [Line Items]
Rate Reduction Bonds - Current Portion	43,200	43,200
Rate Reduction Bonds - Long-Term Portion	345,700	367,300
PSNH \| Securitized Stranded Costs
Condensed Balance Sheet Statements, Captions [Line Items]
Securitized Stranded Cost (included in Regulatory Assets)	381,700	392,500
PSNH \| Securitized Stranded Costs \| VIE
Condensed Balance Sheet Statements, Captions [Line Items]
Securitized Stranded Cost (included in Regulatory Assets)	381,700	392,500
PSNH \| Other Regulatory Assets
Condensed Balance Sheet Statements, Captions [Line Items]
Securitized Stranded Cost (included in Regulatory Assets)	6,800	8,000
PSNH \| Other Regulatory Assets \| VIE
Condensed Balance Sheet Statements, Captions [Line Items]
Regulatory Liabilities	5,700	5,300
Accrued Interest (included in Other Current Liabilities)	2,400	6,300
PSNH \| Current Derivative Assets
Condensed Balance Sheet Statements, Captions [Line Items]
Restricted Cash	17,000	31,600
PSNH \| Current Derivative Assets \| VIE
Condensed Balance Sheet Statements, Captions [Line Items]
Restricted Cash	15,500	30,000
PSNH \| Other Long-Term Assets
Condensed Balance Sheet Statements, Captions [Line Items]
Restricted Cash	3,200	3,200
PSNH \| Other Long-Term Assets \| VIE
Condensed Balance Sheet Statements, Captions [Line Items]
Restricted Cash	$ 3,200	$ 3,200

RATE REDUCTION BONDS AND VARI_5

RATE REDUCTION BONDS AND VARIABLE INTEREST ENTITIES - Summary of the Impact of Funding on the Income Statements (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Condensed Income Statements, Captions [Line Items]
Interest Expense on RRB Principal (included in Interest Expense)	$ 250,749	$ 194,543
PSNH
Condensed Income Statements, Captions [Line Items]
Amortization of RRB Principal (included in Amortization of Regulatory Assets/(Liabilities), Net)	(21,264)	5,317
Interest Expense on RRB Principal (included in Interest Expense)	19,194	17,542
PSNH \| VIE \| Rate Reduction Bonds
Condensed Income Statements, Captions [Line Items]
Amortization of RRB Principal (included in Amortization of Regulatory Assets/(Liabilities), Net)	10,800	10,800
Interest Expense on RRB Principal (included in Interest Expense)	$ 3,700	$ 4,100

PENSION BENEFITS AND POSTRETI_3

PENSION BENEFITS AND POSTRETIREMENT BENEFITS OTHER THAN PENSION - Components of Net Periodic Benefit Expense/(Income) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Pension and SERP
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Service Cost	$ 10.8	$ 11
Interest Cost	62	63.7
Expected Return on Plan Assets	(115.6)	(115.9)
Actuarial Loss/(Gain)	19.8	12.5
Prior Service Cost/(Credit)	0.3	0.3
Settlement Loss	4.3
Total Net Periodic Benefit Plan Income	(18.4)	(28.4)
PBOP
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Service Cost	1.7	1.8
Interest Cost	8	8.5
Expected Return on Plan Assets	(20.4)	(19.1)
Actuarial Loss/(Gain)	(0.1)	0
Prior Service Cost/(Credit)	(5.4)	(5.4)
Settlement Loss	0
Total Net Periodic Benefit Plan Income	(16.2)	(14.2)
CL&P \| Pension and SERP
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Service Cost	2.9	3
Interest Cost	12.4	12.6
Expected Return on Plan Assets	(23.3)	(23.4)
Actuarial Loss/(Gain)	2.5	0.8
Prior Service Cost/(Credit)	0	0
Settlement Loss	0
Total Net Periodic Benefit Plan Income	(5.5)	(7)
Intercompany Expense/(Income) Allocations	0.3	(2)
CL&P \| PBOP
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Service Cost	0.3	0.3
Interest Cost	1.4	1.6
Expected Return on Plan Assets	(2.4)	(2.4)
Actuarial Loss/(Gain)	0	0
Prior Service Cost/(Credit)	0.3	0.3
Settlement Loss	0
Total Net Periodic Benefit Plan Income	(0.4)	(0.2)
Intercompany Expense/(Income) Allocations	(0.6)	(0.5)
NSTAR Electric \| Pension and SERP
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Service Cost	2.1	2.1
Interest Cost	13.1	13.5
Expected Return on Plan Assets	(28.3)	(28.4)
Actuarial Loss/(Gain)	6.4	4.9
Prior Service Cost/(Credit)	0.1	0.1
Settlement Loss	0
Total Net Periodic Benefit Plan Income	(6.6)	(7.8)
Intercompany Expense/(Income) Allocations	0.4	(1.7)
NSTAR Electric \| PBOP
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Service Cost	0.3	0.3
Interest Cost	2.2	2.3
Expected Return on Plan Assets	(9.9)	(9.2)
Actuarial Loss/(Gain)	0	0
Prior Service Cost/(Credit)	(4.2)	(4.2)
Settlement Loss	0
Total Net Periodic Benefit Plan Income	(11.6)	(10.8)
Intercompany Expense/(Income) Allocations	(0.7)	(0.6)
PSNH \| Pension and SERP
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Service Cost	1	1.1
Interest Cost	6.7	6.8
Expected Return on Plan Assets	(12.2)	(12.3)
Actuarial Loss/(Gain)	1.1	0.4
Prior Service Cost/(Credit)	0	0
Settlement Loss	0
Total Net Periodic Benefit Plan Income	(3.4)	(4)
Intercompany Expense/(Income) Allocations	0.1	(0.5)
PSNH \| PBOP
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Service Cost	0.1	0.2
Interest Cost	0.9	0.9
Expected Return on Plan Assets	(1.4)	(1.4)
Actuarial Loss/(Gain)	0	0
Prior Service Cost/(Credit)	0.1	0.1
Settlement Loss	0
Total Net Periodic Benefit Plan Income	(0.3)	(0.2)
Intercompany Expense/(Income) Allocations	$ (0.2)	$ (0.2)

COMMITMENTS AND CONTINGENCIES -

COMMITMENTS AND CONTINGENCIES - Environmental Sites and Related Reserves (Details) $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2024 USD ($) site	Dec. 31, 2023 USD ($) site
Site Contingency [Line Items]
Number of Sites \| site	66	65
Reserve \| $	$ 128	$ 128.2
CL&P
Site Contingency [Line Items]
Number of Sites \| site	16	16
Reserve \| $	$ 13.8	$ 13.8
NSTAR Electric
Site Contingency [Line Items]
Number of Sites \| site	13	12
Reserve \| $	$ 5.9	$ 5.4
PSNH
Site Contingency [Line Items]
Number of Sites \| site	8	8
Reserve \| $	$ 7.7	$ 7.6

COMMITMENTS AND CONTINGENCIES_2

COMMITMENTS AND CONTINGENCIES - Environmental Matters Narrative (Details) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Site Contingency [Line Items]
Reserve balance	$ 128	$ 128.2
MGP Sites
Site Contingency [Line Items]
Reserve balance	$ 116.1	$ 117.1

COMMITMENTS AND CONTINGENCIES_3

COMMITMENTS AND CONTINGENCIES - Long-Term Contractual Arrangements (Details) $ in Millions	Dec. 31, 2023 USD ($)
Renewable Energy Contracts \| PSNH
Unrecorded Unconditional Purchase Obligation [Line Items]
Unrecorded unconditional purchase obligation	$ 503.2

COMMITMENTS AND CONTINGENCIES_4

COMMITMENTS AND CONTINGENCIES - Guarantees and Indemnifications Narrative (Details) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Commitments and Contingencies Disclosure [Abstract]
Fair value of guarantees	$ 2.6	$ 4.4

COMMITMENTS AND CONTINGENCIES_5

COMMITMENTS AND CONTINGENCIES - Schedule of Guarantees and Indemnifications (Details) $ in Millions	Mar. 31, 2024 USD ($) bond	Jan. 24, 2024	Dec. 31, 2023 USD ($)
Guarantor Obligations [Line Items]
Maximum exposure guarantee	$ 2.6		$ 4.4
Eversource Investment LLC \| Letters of Credit
Guarantor Obligations [Line Items]
Maximum Exposure	23.2
Maximum borrowing capacity	$ 25
North East Offshore, LLC, Sunrise Wind LLC, Revolution Wind, LLC and South Fork Wind, LLC
Guarantor Obligations [Line Items]
Ownership interest (percent)	50%
Sunrise Wind LLC
Guarantor Obligations [Line Items]
Ownership interest (percent)		50%
South Fork Wind, LLC
Guarantor Obligations [Line Items]
Maximum Exposure	$ 7.1
Ownership interest (percent)	50%
Eversource Investment LLC and South Fork Class B Member, LLC
Guarantor Obligations [Line Items]
Maximum Exposure	$ 1,520
South Fork Class B Member, LLC
Guarantor Obligations [Line Items]
Ownership interest (percent)	50%
OREC capacity production \| Sunrise Wind LLC
Guarantor Obligations [Line Items]
Maximum Exposure	$ 15.4
Ownership interest (percent)	50%
Tax Equity \| Eversource TEI LLC
Guarantor Obligations [Line Items]
Maximum Exposure	$ 50
North East Offshore, LLC, Sunrise Wind LLC, Revolution Wind, LLC and South Fork Wind, LLC \| Construction-related purchase agreements with third-party contractors
Guarantor Obligations [Line Items]
Maximum Exposure	1,824.3
North East Offshore, LLC, Sunrise Wind LLC, Revolution Wind, LLC and South Fork Wind, LLC \| Performance Guarantee
Guarantor Obligations [Line Items]
Maximum Exposure	3,020
Eversource Investment LLC and South Fork Class B Member, LLC \| Funding and indemnification obligations of North East Offshore LLC
Guarantor Obligations [Line Items]
Maximum Exposure	458.5
Sunrise Wind LLC \| OREC capacity production
Guarantor Obligations [Line Items]
Maximum Exposure	15.4
Sunrise Wind LLC \| Surety Bond
Guarantor Obligations [Line Items]
Maximum Exposure	$ 48.2
Number of surety bonds expiring before full performance completed \| bond	1
South Fork Wind, LLC \| Power Purchase Guarantee
Guarantor Obligations [Line Items]
Maximum Exposure	$ 7.1
Eversource Investment LLC \| Letters Of Credit Guarantee
Guarantor Obligations [Line Items]
Maximum Exposure	23.2
Eversource TEI LLC \| South Fork Wind Tax Equity
Guarantor Obligations [Line Items]
Maximum Exposure	50
Various Eversource subsidiaries \| Surety Bond
Guarantor Obligations [Line Items]
Maximum Exposure	38.8
North East Offshore LLC \| Payment Guarantee
Guarantor Obligations [Line Items]
Maximum Exposure	$ 62.5
Percent of obligations guaranteed (in percent)	50%

COMMITMENTS AND CONTINGENCIES_6

COMMITMENTS AND CONTINGENCIES - Spent Nuclear Fuel Obligations - Yankee Companies (Details) - Yankee Companies - USD ($) $ in Millions	Jun. 08, 2022	Mar. 25, 2021
Loss Contingencies [Line Items]
Damages sought	$ 33.1
CYAPC, YAEC, and MYAPC
Loss Contingencies [Line Items]
Damages sought		$ 120.4

COMMITMENTS AND CONTINGENCIES_7

COMMITMENTS AND CONTINGENCIES - FERC ROE Complaints (Details) $ in Millions			3 Months Ended	36 Months Ended
	Apr. 29, 2016 complaint	Oct. 16, 2014	Mar. 31, 2024 USD ($) period	Oct. 15, 2014	Dec. 31, 2023 USD ($)	Dec. 23, 2019 complaint	Nov. 21, 2019 complaint	Oct. 16, 2018 complaint	Jul. 31, 2014 complaint
Loss Contingencies [Line Items]
Percentage of base ROE reasonably justified (in percent)			10.41%
Percentage of incentive cap on total ROE (in percent)			13.08%
FERC ROE Complaints
Loss Contingencies [Line Items]
Number of complaints filed \| complaint	4					4	2	4
Period of complaint			15 months
Basis point change			0.10%
Estimate of possible loss for each 10 basis point change to base ROE			$ 3
Number of complain periods \| period			4
FERC ROE First, Second and Third Complaints
Loss Contingencies [Line Items]
Number of complaints filed \| complaint									3
Base ROE subsequently authorized			11.14%
FERC ROE First, Second and Third Complaints \| Minimum
Loss Contingencies [Line Items]
Percentage of maximum ROE for any incentive project				11.14%
FERC ROE First, Second and Third Complaints \| Maximum
Loss Contingencies [Line Items]
Percentage of maximum ROE for any incentive project				13.10%
FERC ROE Fourth Complaint
Loss Contingencies [Line Items]
Base ROE percentage of complaint period	10.57%
Maximum percentage cap of ROE for incentive projects	11.74%
FERC ROE First Complaint
Loss Contingencies [Line Items]
Base ROE subsequently authorized		10.57%
Percentage of maximum ROE for any incentive project		11.74%
Amounts associated with first complaint refunded			$ 38.9
FERC ROE First Complaint \| CL&P
Loss Contingencies [Line Items]
Amounts associated with first complaint refunded			22.4
FERC ROE First Complaint \| NSTAR Electric
Loss Contingencies [Line Items]
Amounts associated with first complaint refunded			13.7
FERC ROE First Complaint \| PSNH
Loss Contingencies [Line Items]
Amounts associated with first complaint refunded			$ 2.8
FERC ROE Second Complaint
Loss Contingencies [Line Items]
Base ROE percentage of complaint period			10.57%
Percentage of maximum ROE for any incentive project			11.74%
Loss contingency, estimate of possible earnings impact			$ 39.1		$ 39.1
FERC ROE Second Complaint \| CL&P
Loss Contingencies [Line Items]
Loss contingency, estimate of possible earnings impact			21.4		21.4
FERC ROE Second Complaint \| NSTAR Electric
Loss Contingencies [Line Items]
Loss contingency, estimate of possible earnings impact			14.6		14.6
FERC ROE Second Complaint \| PSNH
Loss Contingencies [Line Items]
Loss contingency, estimate of possible earnings impact			$ 3.1		$ 3.1

FAIR VALUE OF FINANCIAL INSTR_3

FAIR VALUE OF FINANCIAL INSTRUMENTS (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Preferred Stock Not Subject to Mandatory Redemption	$ 155,568	$ 155,569
Rate Reduction Bonds	345,677	367,282
Carrying Amount
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Preferred Stock Not Subject to Mandatory Redemption	155,600	155,600
Long-Term Debt	25,795,200	24,413,500
Rate Reduction Bonds	388,900	410,500
Fair Value \| Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Preferred Stock Not Subject to Mandatory Redemption	123,000	122,200
Long-Term Debt	23,895,800	22,855,200
Rate Reduction Bonds	369,300	395,000
CL&P
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Preferred Stock Not Subject to Mandatory Redemption	116,200	116,200
CL&P \| Carrying Amount
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Preferred Stock Not Subject to Mandatory Redemption	116,200	116,200
Long-Term Debt	4,953,900	4,814,400
Rate Reduction Bonds	0	0
CL&P \| Fair Value \| Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Preferred Stock Not Subject to Mandatory Redemption	90,700	90,400
Long-Term Debt	4,615,200	4,572,000
Rate Reduction Bonds	0	0
NSTAR Electric
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Preferred Stock Not Subject to Mandatory Redemption	43,000	43,000
NSTAR Electric \| Carrying Amount
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Preferred Stock Not Subject to Mandatory Redemption	43,000	43,000
Long-Term Debt	4,498,000	4,496,900
Rate Reduction Bonds	0	0
NSTAR Electric \| Fair Value \| Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Preferred Stock Not Subject to Mandatory Redemption	32,300	31,800
Long-Term Debt	4,186,000	4,273,700
Rate Reduction Bonds	0	0
PSNH
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Rate Reduction Bonds	345,677	367,282
PSNH \| Carrying Amount
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Preferred Stock Not Subject to Mandatory Redemption	0	0
Long-Term Debt	1,682,700	1,431,600
Rate Reduction Bonds	388,900	410,500
PSNH \| Fair Value \| Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Preferred Stock Not Subject to Mandatory Redemption	0	0
Long-Term Debt	1,508,400	1,292,600
Rate Reduction Bonds	$ 369,300	$ 395,000

ACCUMULATED OTHER COMPREHENSI_3

ACCUMULATED OTHER COMPREHENSIVE INCOME/(LOSS) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
AOCI Attributable to Parent [Roll Forward]
Amounts Reclassified from AOCI	$ 5,200	$ 3,200
Other Comprehensive Income, Net of Tax	5,203	3,230
Accumulated Other Comprehensive Loss
AOCI Attributable to Parent [Roll Forward]
Balance as of Beginning of Period	(33,700)	(39,400)
Other Comprehensive Income, Net of Tax	5,203	3,230
Balance as of End of Period	(28,500)	(36,200)
Qualified Cash Flow Hedging Instruments
AOCI Attributable to Parent [Roll Forward]
Balance as of Beginning of Period	(400)	(400)
Amounts Reclassified from AOCI	0	0
Other Comprehensive Income, Net of Tax	0	0
Balance as of End of Period	(400)	(400)
Unrealized Gains/(Losses) on Marketable Securities
AOCI Attributable to Parent [Roll Forward]
Balance as of Beginning of Period		(1,200)
Amounts Reclassified from AOCI		1,200
Other Comprehensive Income, Net of Tax		1,200
Balance as of End of Period		0
Defined Benefit Plans
AOCI Attributable to Parent [Roll Forward]
Balance as of Beginning of Period	(33,300)	(37,800)
Amounts Reclassified from AOCI	5,200	2,000
Other Comprehensive Income, Net of Tax	5,200	2,000
Balance as of End of Period	$ (28,100)	$ (35,800)

COMMON SHARES - Common Shares A

COMMON SHARES - Common Shares Authorized and Issued (Details) - $ / shares	Mar. 31, 2024	Dec. 31, 2023
Class of Stock [Line Items]
Par value (in dollars per share)	$ 5	$ 5
Authorized (in shares)	410,000,000	410,000,000
Issued (in shares)	361,276,965	359,984,073
CL&P
Class of Stock [Line Items]
Par value (in dollars per share)	$ 10	$ 10
Authorized (in shares)	24,500,000	24,500,000
Issued (in shares)	6,035,205	6,035,205
NSTAR Electric
Class of Stock [Line Items]
Par value (in dollars per share)	$ 1	$ 1
Authorized (in shares)	100,000,000	100,000,000
Issued (in shares)	200	200
PSNH
Class of Stock [Line Items]
Par value (in dollars per share)	$ 1	$ 1
Authorized (in shares)	100,000,000	100,000,000
Issued (in shares)	301	301

COMMON SHARES - Narrative (Deta

COMMON SHARES - Narrative (Details) - USD ($) $ in Millions		3 Months Ended	12 Months Ended
COMMON SHARES - Narrative (Details) - USD ($) $ in Millions	May 11, 2022	Mar. 31, 2024	Dec. 31, 2023
Equity [Abstract]
Sale of stock, issuance of common stock, maximum	$ 1,200
Sale of stock, consideration received on transaction		$ 75.4
Sale of stock, number of shares issued in transaction (in shares)		1,292,892	0
Treasury stock, common (in shares)		9,897,551	10,443,807
Common stock outstanding (in shares)		351,379,414	349,540,266

COMMON SHAREHOLDERS' EQUITY A_2

COMMON SHAREHOLDERS' EQUITY AND NONCONTROLLING INTERESTS (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023
Noncontrolling Interest [Line Items]
Dividends on preferred stock	$ 1,880	$ 1,880
Noncontrolling interest attributed to preferred stock of subsidiaries	155,568		$ 155,569
CL&P and NSTAR
Noncontrolling Interest [Line Items]
Dividends on preferred stock	$ 1,900	$ 1,900

EARNINGS PER SHARE - Narrative

EARNINGS PER SHARE - Narrative (Details) - shares	3 Months Ended
EARNINGS PER SHARE - Narrative (Details) - shares	Mar. 31, 2024	Mar. 31, 2023
Earnings Per Share [Abstract]
Antidilutive share awards excluded from the EPS computation (in shares)	0	0

EARNINGS PER SHARE - Components

EARNINGS PER SHARE - Components of Basic and Diluted EPS (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Earnings Per Share [Abstract]
Net Income Attributable to Common Shareholders	$ 521,848	$ 491,159
Net Income Attributable to Common Shareholders	$ 521,800	$ 491,200
Weighted Average Common Shares Outstanding:
Basic (in shares)	350,717,114	349,217,147
Dilutive effect (in shares)	280,106	394,866
Diluted (in shares)	350,997,220	349,612,013
Basic EPS (in dollars per share)	$ 1.49	$ 1.41
Diluted EPS (in dollars per share)	$ 1.49	$ 1.41

REVENUES (Details)

REVENUES (Details) - USD ($) $ in Thousands	3 Months Ended
REVENUES (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Mar. 31, 2023
Disaggregation of Revenue [Line Items]
Revenues from Contracts with Customers	$ 3,276,800	$ 3,751,800
Alternative Revenue Programs	49,100	36,900
Other Revenues	6,700	6,900
Operating Revenues	3,332,575	3,795,643
CL&P
Disaggregation of Revenue [Line Items]
Operating Revenues	1,121,291	1,338,905
NSTAR Electric
Disaggregation of Revenue [Line Items]
Operating Revenues	947,615	956,283
PSNH
Disaggregation of Revenue [Line Items]
Operating Revenues	326,116	420,155
Total Retail Tariff Sales Revenues
Disaggregation of Revenue [Line Items]
Revenues from Contracts with Customers	2,904,500	3,347,100
Residential
Disaggregation of Revenue [Line Items]
Revenues from Contracts with Customers	1,792,000	2,069,500
Commercial
Disaggregation of Revenue [Line Items]
Revenues from Contracts with Customers	969,100	1,122,900
Industrial
Disaggregation of Revenue [Line Items]
Revenues from Contracts with Customers	143,400	154,700
Wholesale Transmission Revenues
Disaggregation of Revenue [Line Items]
Revenues from Contracts with Customers	112,500	109,700
Wholesale Market Sales Revenues
Disaggregation of Revenue [Line Items]
Revenues from Contracts with Customers	224,400	267,200
Other Revenues from Contracts with Customers
Disaggregation of Revenue [Line Items]
Revenues from Contracts with Customers	35,400	27,800
Operating Segments \| CL&P
Disaggregation of Revenue [Line Items]
Revenues from Contracts with Customers	1,250,800	1,451,800
Alternative Revenue Programs	27,400	24,600
Other Revenues	2,900	2,200
Operating Segments \| NSTAR Electric
Disaggregation of Revenue [Line Items]
Revenues from Contracts with Customers	1,097,100	1,104,400
Alternative Revenue Programs	7,800	(9,500)
Other Revenues	2,000	2,500
Operating Segments \| PSNH
Disaggregation of Revenue [Line Items]
Revenues from Contracts with Customers	373,900	461,100
Alternative Revenue Programs	7,600	9,600
Other Revenues	800	1,000
Operating Segments \| Total Retail Tariff Sales Revenues \| CL&P
Disaggregation of Revenue [Line Items]
Revenues from Contracts with Customers	912,500	1,091,400
Operating Segments \| Total Retail Tariff Sales Revenues \| NSTAR Electric
Disaggregation of Revenue [Line Items]
Revenues from Contracts with Customers	865,600	884,700
Operating Segments \| Total Retail Tariff Sales Revenues \| PSNH
Disaggregation of Revenue [Line Items]
Revenues from Contracts with Customers	271,600	365,200
Operating Segments \| Residential \| CL&P
Disaggregation of Revenue [Line Items]
Revenues from Contracts with Customers	626,800	762,200
Operating Segments \| Residential \| NSTAR Electric
Disaggregation of Revenue [Line Items]
Revenues from Contracts with Customers	462,200	467,800
Operating Segments \| Residential \| PSNH
Disaggregation of Revenue [Line Items]
Revenues from Contracts with Customers	165,100	234,000
Operating Segments \| Commercial \| CL&P
Disaggregation of Revenue [Line Items]
Revenues from Contracts with Customers	252,400	295,300
Operating Segments \| Commercial \| NSTAR Electric
Disaggregation of Revenue [Line Items]
Revenues from Contracts with Customers	373,500	384,300
Operating Segments \| Commercial \| PSNH
Disaggregation of Revenue [Line Items]
Revenues from Contracts with Customers	82,000	108,600
Operating Segments \| Industrial \| CL&P
Disaggregation of Revenue [Line Items]
Revenues from Contracts with Customers	33,300	33,900
Operating Segments \| Industrial \| NSTAR Electric
Disaggregation of Revenue [Line Items]
Revenues from Contracts with Customers	29,900	32,600
Operating Segments \| Industrial \| PSNH
Disaggregation of Revenue [Line Items]
Revenues from Contracts with Customers	24,500	22,600
Operating Segments \| Wholesale Transmission Revenues \| CL&P
Disaggregation of Revenue [Line Items]
Revenues from Contracts with Customers	200,700	195,800
Operating Segments \| Wholesale Transmission Revenues \| NSTAR Electric
Disaggregation of Revenue [Line Items]
Revenues from Contracts with Customers	188,800	167,800
Operating Segments \| Wholesale Transmission Revenues \| PSNH
Disaggregation of Revenue [Line Items]
Revenues from Contracts with Customers	84,600	71,400
Operating Segments \| Wholesale Market Sales Revenues \| CL&P
Disaggregation of Revenue [Line Items]
Revenues from Contracts with Customers	121,200	154,600
Operating Segments \| Wholesale Market Sales Revenues \| NSTAR Electric
Disaggregation of Revenue [Line Items]
Revenues from Contracts with Customers	31,600	41,100
Operating Segments \| Wholesale Market Sales Revenues \| PSNH
Disaggregation of Revenue [Line Items]
Revenues from Contracts with Customers	12,500	21,600
Operating Segments \| Other Revenues from Contracts with Customers \| CL&P
Disaggregation of Revenue [Line Items]
Revenues from Contracts with Customers	16,400	10,000
Operating Segments \| Other Revenues from Contracts with Customers \| NSTAR Electric
Disaggregation of Revenue [Line Items]
Revenues from Contracts with Customers	11,100	10,800
Operating Segments \| Other Revenues from Contracts with Customers \| PSNH
Disaggregation of Revenue [Line Items]
Revenues from Contracts with Customers	5,200	2,900
Other
Disaggregation of Revenue [Line Items]
Revenues from Contracts with Customers	443,600	413,800
Alternative Revenue Programs	0	0
Other Revenues	0	0
Operating Revenues	443,600	413,800
Other \| Total Retail Tariff Sales Revenues
Disaggregation of Revenue [Line Items]
Revenues from Contracts with Customers	0	0
Other \| Residential
Disaggregation of Revenue [Line Items]
Revenues from Contracts with Customers	0	0
Other \| Commercial
Disaggregation of Revenue [Line Items]
Revenues from Contracts with Customers	0	0
Other \| Industrial
Disaggregation of Revenue [Line Items]
Revenues from Contracts with Customers	0	0
Other \| Wholesale Transmission Revenues
Disaggregation of Revenue [Line Items]
Revenues from Contracts with Customers	0	0
Other \| Wholesale Market Sales Revenues
Disaggregation of Revenue [Line Items]
Revenues from Contracts with Customers	0	0
Other \| Other Revenues from Contracts with Customers
Disaggregation of Revenue [Line Items]
Revenues from Contracts with Customers	443,600	413,800
Eliminations
Disaggregation of Revenue [Line Items]
Revenues from Contracts with Customers	(809,800)	(744,000)
Alternative Revenue Programs	(26,800)	(16,900)
Other Revenues	0	0
Operating Revenues	(836,600)	(760,900)
Eliminations \| Total Retail Tariff Sales Revenues
Disaggregation of Revenue [Line Items]
Revenues from Contracts with Customers	(6,800)	(6,100)
Eliminations \| Residential
Disaggregation of Revenue [Line Items]
Revenues from Contracts with Customers	0	0
Eliminations \| Commercial
Disaggregation of Revenue [Line Items]
Revenues from Contracts with Customers	(1,700)	(1,000)
Eliminations \| Industrial
Disaggregation of Revenue [Line Items]
Revenues from Contracts with Customers	(5,100)	(5,100)
Eliminations \| Wholesale Transmission Revenues
Disaggregation of Revenue [Line Items]
Revenues from Contracts with Customers	(361,600)	(325,300)
Eliminations \| Wholesale Market Sales Revenues
Disaggregation of Revenue [Line Items]
Revenues from Contracts with Customers	0	0
Eliminations \| Other Revenues from Contracts with Customers
Disaggregation of Revenue [Line Items]
Revenues from Contracts with Customers	(441,400)	(412,600)
Consolidations Eliminations \| CL&P
Disaggregation of Revenue [Line Items]
Operating Revenues	(159,800)	(139,700)
Consolidations Eliminations \| NSTAR Electric
Disaggregation of Revenue [Line Items]
Operating Revenues	(159,300)	(141,100)
Consolidations Eliminations \| PSNH
Disaggregation of Revenue [Line Items]
Operating Revenues	(56,200)	(51,500)
Electric Distribution \| Operating Segments
Disaggregation of Revenue [Line Items]
Revenues from Contracts with Customers	2,243,000	2,577,100
Alternative Revenue Programs	13,200	6,000
Other Revenues	5,500	5,500
Operating Revenues	2,261,700	2,588,600
Electric Distribution \| Operating Segments \| Total Retail Tariff Sales Revenues
Disaggregation of Revenue [Line Items]
Revenues from Contracts with Customers	2,049,300	2,341,500
Electric Distribution \| Operating Segments \| Residential
Disaggregation of Revenue [Line Items]
Revenues from Contracts with Customers	1,254,100	1,464,000
Electric Distribution \| Operating Segments \| Commercial
Disaggregation of Revenue [Line Items]
Revenues from Contracts with Customers	707,500	788,400
Electric Distribution \| Operating Segments \| Industrial
Disaggregation of Revenue [Line Items]
Revenues from Contracts with Customers	87,700	89,100
Electric Distribution \| Operating Segments \| Wholesale Transmission Revenues
Disaggregation of Revenue [Line Items]
Revenues from Contracts with Customers	0	0
Electric Distribution \| Operating Segments \| Wholesale Market Sales Revenues
Disaggregation of Revenue [Line Items]
Revenues from Contracts with Customers	165,300	217,300
Electric Distribution \| Operating Segments \| Other Revenues from Contracts with Customers
Disaggregation of Revenue [Line Items]
Revenues from Contracts with Customers	28,400	18,300
Natural Gas Distribution \| Operating Segments
Disaggregation of Revenue [Line Items]
Revenues from Contracts with Customers	873,800	1,016,800
Alternative Revenue Programs	31,500	27,400
Other Revenues	700	1,000
Operating Revenues	906,000	1,045,200
Natural Gas Distribution \| Operating Segments \| Total Retail Tariff Sales Revenues
Disaggregation of Revenue [Line Items]
Revenues from Contracts with Customers	814,500	966,200
Natural Gas Distribution \| Operating Segments \| Residential
Disaggregation of Revenue [Line Items]
Revenues from Contracts with Customers	507,600	576,600
Natural Gas Distribution \| Operating Segments \| Commercial
Disaggregation of Revenue [Line Items]
Revenues from Contracts with Customers	247,100	320,000
Natural Gas Distribution \| Operating Segments \| Industrial
Disaggregation of Revenue [Line Items]
Revenues from Contracts with Customers	59,800	69,600
Natural Gas Distribution \| Operating Segments \| Wholesale Transmission Revenues
Disaggregation of Revenue [Line Items]
Revenues from Contracts with Customers	0	0
Natural Gas Distribution \| Operating Segments \| Wholesale Market Sales Revenues
Disaggregation of Revenue [Line Items]
Revenues from Contracts with Customers	58,200	49,100
Natural Gas Distribution \| Operating Segments \| Other Revenues from Contracts with Customers
Disaggregation of Revenue [Line Items]
Revenues from Contracts with Customers	1,100	1,500
Electric Transmission \| Operating Segments
Disaggregation of Revenue [Line Items]
Revenues from Contracts with Customers	478,000	439,700
Alternative Revenue Programs	29,600	18,700
Other Revenues	200	200
Operating Revenues	507,800	458,600
Electric Transmission \| Operating Segments \| Total Retail Tariff Sales Revenues
Disaggregation of Revenue [Line Items]
Revenues from Contracts with Customers	0	0
Electric Transmission \| Operating Segments \| Residential
Disaggregation of Revenue [Line Items]
Revenues from Contracts with Customers	0	0
Electric Transmission \| Operating Segments \| Commercial
Disaggregation of Revenue [Line Items]
Revenues from Contracts with Customers	0	0
Electric Transmission \| Operating Segments \| Industrial
Disaggregation of Revenue [Line Items]
Revenues from Contracts with Customers	0	0
Electric Transmission \| Operating Segments \| Wholesale Transmission Revenues
Disaggregation of Revenue [Line Items]
Revenues from Contracts with Customers	474,100	435,000
Electric Transmission \| Operating Segments \| Wholesale Market Sales Revenues
Disaggregation of Revenue [Line Items]
Revenues from Contracts with Customers	0	0
Electric Transmission \| Operating Segments \| Other Revenues from Contracts with Customers
Disaggregation of Revenue [Line Items]
Revenues from Contracts with Customers	3,900	4,700
Water Distribution \| Operating Segments
Disaggregation of Revenue [Line Items]
Revenues from Contracts with Customers	48,200	48,400
Alternative Revenue Programs	1,600	1,700
Other Revenues	300	200
Operating Revenues	50,100	50,300
Water Distribution \| Operating Segments \| Total Retail Tariff Sales Revenues
Disaggregation of Revenue [Line Items]
Revenues from Contracts with Customers	47,500	45,500
Water Distribution \| Operating Segments \| Residential
Disaggregation of Revenue [Line Items]
Revenues from Contracts with Customers	30,300	28,900
Water Distribution \| Operating Segments \| Commercial
Disaggregation of Revenue [Line Items]
Revenues from Contracts with Customers	16,200	15,500
Water Distribution \| Operating Segments \| Industrial
Disaggregation of Revenue [Line Items]
Revenues from Contracts with Customers	1,000	1,100
Water Distribution \| Operating Segments \| Wholesale Transmission Revenues
Disaggregation of Revenue [Line Items]
Revenues from Contracts with Customers	0	0
Water Distribution \| Operating Segments \| Wholesale Market Sales Revenues
Disaggregation of Revenue [Line Items]
Revenues from Contracts with Customers	900	800
Water Distribution \| Operating Segments \| Other Revenues from Contracts with Customers
Disaggregation of Revenue [Line Items]
Revenues from Contracts with Customers	$ (200)	$ 2,100

SEGMENT INFORMATION - Narrative

SEGMENT INFORMATION - Narrative (Details) $ in Millions	3 Months Ended
SEGMENT INFORMATION - Narrative (Details) $ in Millions	Mar. 31, 2024 USD ($) reportableSegment
CL&P
Segment Reporting Information [Line Items]
Number of reportable segments	1
NSTAR Electric
Segment Reporting Information [Line Items]
Number of reportable segments	1
PSNH
Segment Reporting Information [Line Items]
Number of reportable segments	1
Related Party
Segment Reporting Information [Line Items]
Amount of natural gas transmission purchased \| $	$ 77.7

SEGMENT INFORMATION - Summary o

SEGMENT INFORMATION - Summary of Segment Information and Segmented Total Assets (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023
Segment Reporting Information [Line Items]
Operating Revenues	$ 3,332,575	$ 3,795,643
Depreciation and Amortization	(337,600)	(236,900)
Other Operating Expenses	(2,149,000)	(2,809,100)
Operating Income/(Loss)	845,973	749,573
Interest Expense	(250,749)	(194,543)
Other Income, Net	91,030	88,981
Net Income/(Loss) Attributable to Common Shareholders	521,848	491,159
Cash Flows Used for Investments in Plant	1,149,400	977,100
Assets	57,322,225		$ 55,612,245
Other
Segment Reporting Information [Line Items]
Operating Revenues	443,600	413,800
Depreciation and Amortization	(45,700)	(36,800)
Other Operating Expenses	(349,500)	(339,600)
Operating Income/(Loss)	48,400	37,400
Interest Expense	(146,100)	(85,100)
Other Income, Net	622,600	565,800
Net Income/(Loss) Attributable to Common Shareholders	540,400	516,900
Cash Flows Used for Investments in Plant	43,000	65,200
Assets	28,358,100		26,337,700
Eliminations
Segment Reporting Information [Line Items]
Operating Revenues	(836,600)	(760,900)
Depreciation and Amortization	2,500	2,100
Other Operating Expenses	834,100	759,300
Operating Income/(Loss)	0	500
Interest Expense	54,700	32,000
Other Income, Net	(614,100)	(550,600)
Net Income/(Loss) Attributable to Common Shareholders	(559,400)	(518,100)
Cash Flows Used for Investments in Plant	0	0
Assets	(28,523,400)		(26,678,500)
Electric Distribution \| Operating Segments
Segment Reporting Information [Line Items]
Operating Revenues	2,261,700	2,588,600
Depreciation and Amortization	(109,800)	(22,000)
Other Operating Expenses	(1,905,100)	(2,342,300)
Operating Income/(Loss)	246,800	224,300
Interest Expense	(82,500)	(69,300)
Other Income, Net	56,600	54,300
Net Income/(Loss) Attributable to Common Shareholders	168,100	165,500
Cash Flows Used for Investments in Plant	471,300	371,900
Assets	30,437,000		29,426,400
Natural Gas Distribution \| Operating Segments
Segment Reporting Information [Line Items]
Operating Revenues	906,000	1,045,200
Depreciation and Amortization	(83,000)	(77,000)
Other Operating Expenses	(554,600)	(730,400)
Operating Income/(Loss)	268,400	237,800
Interest Expense	(24,500)	(21,200)
Other Income, Net	10,100	9,000
Net Income/(Loss) Attributable to Common Shareholders	190,600	170,300
Cash Flows Used for Investments in Plant	244,800	165,500
Assets	8,948,500		8,775,300
Electric Transmission \| Operating Segments
Segment Reporting Information [Line Items]
Operating Revenues	507,800	458,600
Depreciation and Amortization	(101,000)	(89,900)
Other Operating Expenses	(141,900)	(128,200)
Operating Income/(Loss)	264,900	240,500
Interest Expense	(40,900)	(41,500)
Other Income, Net	14,100	9,400
Net Income/(Loss) Attributable to Common Shareholders	176,700	155,100
Cash Flows Used for Investments in Plant	358,400	336,600
Assets	15,129,800		14,806,500
Water Distribution \| Operating Segments
Segment Reporting Information [Line Items]
Operating Revenues	50,100	50,300
Depreciation and Amortization	(600)	(13,300)
Other Operating Expenses	(32,000)	(27,900)
Operating Income/(Loss)	17,500	9,100
Interest Expense	(11,400)	(9,400)
Other Income, Net	1,700	1,100
Net Income/(Loss) Attributable to Common Shareholders	5,400	1,500
Cash Flows Used for Investments in Plant	31,900	$ 37,900
Assets	$ 2,972,200		$ 2,944,800