Consolidated Statements of Revenues and Expenses (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Operating revenues:
Total operating revenues	$ 500,776	$ 704,265	$ 1,279,618	$ 1,657,835
Operating expenses:
Fuel	184,766	419,218	450,402	847,823
Production	102,418	114,167	295,297	323,334
Depreciation and amortization	86,323	70,926	232,012	212,682
Purchased power	18,213	21,383	53,628	55,919
Accretion	16,739	14,018	48,969	41,410
Total operating expenses	408,459	639,712	1,080,308	1,481,168
Operating margin	92,317	64,553	199,310	176,667
Other income:
Investment income	17,233	15,090	51,558	39,762
Other	3,562	3,385	9,396	9,510
Total other income	20,795	18,475	60,954	49,272
Interest charges:
Interest expense	132,538	117,018	384,629	333,282
Allowance for debt funds used during construction	(49,185)	(69,031)	(202,206)	(188,301)
Amortization of debt discount and expense	2,632	2,944	7,890	8,714
Net interest charges	85,985	50,931	190,313	153,695
Net margin	27,127	32,097	69,951	72,244
Members
Operating revenues:
Total operating revenues	471,488	627,130	1,224,637	1,523,361
Non-Members
Operating revenues:
Total operating revenues	$ 29,288	$ 77,135	$ 54,981	$ 134,474