Consolidated Statements of Revenues and Expenses (Unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Operating revenues:
Total operating revenues	$ 389,389	$ 533,128	$ 778,842	$ 953,570
Operating expenses:
Fuel	132,468	263,121	265,636	428,605
Production	99,412	113,387	192,879	209,167
Depreciation and amortization	73,015	70,830	145,689	141,756
Purchased power	17,785	17,661	35,415	34,536
Accretion	16,722	13,860	32,230	27,392
Total operating expenses	339,402	478,859	671,849	841,456
Operating margin	49,987	54,269	106,993	112,114
Other income:
Investment income	17,943	12,825	34,325	24,672
Other	2,909	3,095	5,834	6,125
Total other income	20,852	15,920	40,159	30,797
Interest charges:
Interest expense	128,384	111,595	252,091	216,264
Allowance for debt funds used during construction	(78,591)	(62,497)	(153,021)	(119,270)
Amortization of debt discount and expense	2,632	2,924	5,258	5,770
Net interest charges	52,425	52,022	104,328	102,764
Net margin	18,414	18,167	42,824	40,147
Members
Operating revenues:
Total operating revenues	365,496	478,782	753,149	896,231
Non-Members
Operating revenues:
Total operating revenues	$ 23,893	$ 54,346	$ 25,693	$ 57,339