Consolidated Statements Of Revenues, Expenses, And Patronage Capital - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Income Statement [Abstract]
Operating Revenues	$ 780,640	$ 807,704	$ 932,682
Revenue, Product and Service [Extensible Enumeration]	us-gaap:ElectricityMember	us-gaap:ElectricityMember	us-gaap:ElectricityMember
Operating Expenses:
Fuel	$ 166,517	$ 144,348	$ 172,921
Purchased power	234,471	250,546	332,216
Transmission	131,290	128,427	159,995
Deferred energy	(28,116)	26,660	22,522
Operations and maintenance	78,294	61,518	74,647
Administrative and general	41,372	43,023	48,938
Depreciation and amortization	70,416	69,902	68,752
Amortization of regulatory asset/(liability), net	16,458	9,069	(35,056)
Accretion of asset retirement obligations	5,664	5,463	5,539
Taxes, other than income taxes	9,171	9,275	9,412
Total Operating Expenses	725,537	748,231	859,886
Operating Margin	55,103	59,473	72,796
Other income (expense), net	409	(105)	(162)
Investment income	20,162	13,106	7,188
Interest charges, net	(55,657)	(60,306)	(62,773)
Income taxes	8	(2)	(25)
Net Margin including Non-controlling interest	20,025	12,166	17,024
Non-controlling interest	22	(7)	(70)
Net Margin attributable to ODEC	20,047	12,159	16,954
Patronage Capital - Beginning of Period	453,470	441,311	428,663
Patronage Capital - Retirement	(8,740)		(4,306)
Patronage Capital - End of Period	$ 464,777	$ 453,470	$ 441,311