CONDENSED CONSOLIDATED STATEMENTS OF INCOME (LOSS) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Utility revenues:
Utility revenues, exclusive of alternative revenue programs	$ 365,142	$ 306,398	$ 1,228,059	$ 1,019,756
Alternative revenue programs	(5,850)	(10,499)	(28,420)	(13,069)
Total utility revenues	359,292	295,899	1,199,639	1,006,687
Non-utility revenues	154	108	419	445
Total operating revenues	359,446	296,007	1,200,058	1,007,132
Utility operating expenses:
Resource costs	147,784	102,133	492,049	327,390
Other operating expenses	101,701	85,625	300,710	267,233
Depreciation and amortization	63,484	57,722	188,867	169,009
Taxes other than income taxes	26,002	25,440	86,777	82,223
Non-utility operating expenses:
Other operating expenses	1,041	843	4,907	3,186
Depreciation and amortization	32	30	94	230
Total operating expenses	340,044	271,793	1,073,404	849,271
Income from operations	19,402	24,214	126,654	157,861
Interest expense	29,533	26,547	86,118	78,982
Interest expense to affiliated trusts	302	102	596	317
Capitalized interest	(828)	(1,102)	(2,853)	(3,033)
Other income-net	(3,964)	(10,267)	(22,749)	(23,992)
Income (loss) before income taxes	(5,641)	8,934	65,542	105,587
Income tax expense (benefit)	157	(5,432)	(11,678)	9,130
Net income (loss)	$ (5,798)	$ 14,366	$ 77,220	$ 96,457
Weighted-average common shares outstanding (thousands), basic	73,229	70,054	72,547	69,582
Weighted-average common shares outstanding (thousands), diluted	73,298	70,129	72,629	69,722
Earnings (loss) per common share:
Basic	$ (0.08)	$ 0.21	$ 1.06	$ 1.39
Diluted	$ (0.08)	$ 0.20	$ 1.06	$ 1.38