Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Cash flows from operating activities
Net income (loss)	$ (1,424,119)	$ 201,128	$ 243,028
Adjustments to reconcile net income (loss) to net cash provided by operating activities-continuing operations
Loss (income) from discontinued operations	103,486	(53,362)	(79,989)
Depreciation of property, plant and equipment	261,701	254,990	244,477
Other amortization	31,832	27,316	25,928
Loss (gains) on sale of equity-method investment	0	644	(8,123)
Deferred income tax expense (benefit)	(486,188)	9,352	(33,157)
Share-based compensation expense	3,591	6,776	7,450
Allowance for equity funds used during construction	(13,786)	(15,164)	(10,574)
Asset impairment	39,642	0	0
Other	(13,790)	(2,989)	(5,323)
Changes in assets and liabilities
Decrease (increase) in accounts receivable and unbilled revenues, net	96,700	(71,643)	(147,327)
Decrease (increase) in fuel oil stock	49,361	43,388	(87,569)
Increase in materials and supplies	(4,177)	(34,887)	(7,960)
Decrease (increase) in regulatory assets	(22,743)	(10,613)	34,600
Increase in regulatory liabilities	48,433	54,470	44,888
Increase in accounts, interest and dividends payable	6,862	34,290	23,083
Change in prepaid and accrued income taxes, tax credits and utility revenue taxes	(25,525)	(9,858)	120,738
Change in defined benefit pension and other postretirement benefit plans asset/liability	(9,358)	(8,215)	(4,564)
Increase in wildfire tort-related claims	1,840,000	75,000	0
Change in other assets and liabilities	(53,812)	(57,255)	(25,924)
Net cash provided by operating activities-continuing operations	428,110	443,368	333,682
Net cash provided by operating activities-discontinued operations	59,371	108,103	120,794
Net cash provided by operating activities	487,481	551,471	454,476
Cash flows from investing activities
Capital expenditures	(344,251)	(442,727)	(339,333)
Acquisition of business	0	0	(25,706)
Other, net	10,330	6,558	14,184
Net cash used in investing activities-continuing operations	(333,921)	(436,169)	(350,855)
Net cash provided by (used in) investing activities-discontinued operations	592,239	178,770	(777,827)
Net cash used in investing activities	258,318	(257,399)	(1,128,682)
Cash flows from financing activities
Net decrease in short-term borrowings with original maturities of three months or less	0	(137,650)	83,652
Proceeds from issuance of short-term debt	50,000	65,000	35,000
Repayment of short-term debt	0	(100,000)	0
Proceeds from issuance of long-term debt	5,475	625,000	227,312
Repayment of long-term debt and funds transferred for repayment of long-term debt	(97,698)	(167,080)	(221,910)
Withheld shares for employee taxes on vested share-based compensation	(1,074)	(2,371)	(3,165)
Net proceeds from issuance of common stock	556,612	1,223	0
Common stock dividends	0	(73,957)	(111,229)
Preferred stock dividends of subsidiaries	(1,890)	(1,890)	(1,890)
Other	(13,867)	(5,133)	(2,041)
Net cash provided by financing activities-continuing operations	497,558	203,142	5,729
Net cash provided by (used in) financing activities-discontinued operations	(342,853)	(7,567)	561,942
Net cash provided by (used in) financing activities	154,705	195,575	567,671
Net increase (decrease) in cash, cash equivalents and restricted cash, including cash from discontinued operations	900,504	489,647	(106,535)
Cash, cash equivalents and restricted cash, including cash from discontinued operations, January 1	694,574	204,927	311,462
Cash, cash equivalents and restricted cash, including cash from discontinued operations, December 31	1,595,078	694,574	204,927
Less: Restricted cash	(492,317)	(15,028)	(5,050)
Less: Cash from discontinued operations	(352,226)	(435,455)	(156,149)
Cash and cash equivalents	$ 750,535	$ 244,091	$ 43,728