CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Operating Activities:
Net Income/(Loss)	$ 1,699,891	$ 819,172	$ (434,721)
Adjustments to Reconcile Net Income/(Loss) to Net Cash Flows Provided by Operating Activities:
Depreciation	1,568,578	1,433,503	1,305,840
Deferred Income Taxes	27,313	435,889	85,405
Uncollectible Expense	101,141	74,069	72,468
Pension, SERP and PBOP Income, Net	(80,628)	(73,564)	(90,706)
Regulatory Over/(Under) Recoveries, Net	13,062	(919,359)	(151,548)
Amortization	835,909	342,864	(490,117)
Cost of Removal Expenditures	(275,906)	(294,984)	(315,699)
Losses on Offshore Wind	284,000	464,019	2,167,000
Loss on Pending Sale of Aquarion	0	297,000	0
Other	(4,826)	(108,365)	(59,886)
Changes in Current Assets and Liabilities:
Receivables and Unbilled Revenues, Net	(364,156)	(432,620)	(124,393)
Taxes Receivable/Accrued, Net	143,331	55,502	36,357
Accounts Payable	84,192	47,082	(287,637)
Other Current Assets and Liabilities, Net	81,671	19,529	(66,202)
Net Cash Flows Provided by Operating Activities	4,113,572	2,159,737	1,646,161
Investing Activities:
Investments in Property, Plant and Equipment	(4,158,669)	(4,480,529)	(4,336,849)
Proceeds from Sales of Marketable Securities	439,311	268,164	395,604
Purchases of Marketable Securities	(416,082)	(242,959)	(336,779)
Payments for Offshore Wind Contingent Liability	(200,842)	0	0
Investments in Unconsolidated Affiliates	(701)	(929,688)	(1,680,473)
Proceeds from Sales of Offshore Wind Investments	0	862,713	1,090,662
Other Investing Activities	30,820	(13,365)	(2,897)
Net Cash Flows Used in Investing Activities	(4,306,163)	(4,535,664)	(4,870,732)
Financing Activities:
Issuance of Common Shares, Net of Issuance Costs	465,389	989,447	0
Cash Dividends on Common Shares	(1,093,074)	(1,001,488)	(918,995)
Cash Dividends on Preferred Stock	(7,519)	(7,519)	(7,519)
(Decrease)/Increase in Notes Payable	(517,348)	(94,959)	695,552
Repayment of Rate Reduction Bonds	(43,210)	(43,210)	(43,210)
Issuance of Long-Term Debt	2,942,353	4,501,623	5,198,345
Retirement of Long-Term Debt	(1,400,331)	(1,949,995)	(2,008,470)
Other Financing Activities	(34,732)	(57,082)	(46,466)
Net Cash Flows Provided by Financing Activities	311,528	2,336,817	2,869,237
Net Increase/(Decrease) in Cash and Restricted Cash	118,937	(39,110)	(355,334)
Cash and Restricted Cash - Beginning of Year	127,308	166,418	521,752
Cash and Restricted Cash - End of Year	$ 246,245	$ 127,308	$ 166,418