Consolidated Statements Of Operations - USD ($)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Consolidated Statements Of Operations [Abstract]
Operating revenues	$ 197,747,579	$ 216,421,152	$ 281,318,513
Operating expenses:
Fuel	54,778,582	66,534,877	126,038,350
Production	15,809,168	16,886,257	21,082,176
Purchased power	15,774,733	19,599,994	15,608,396
Transmission	5,590,737	6,287,558	6,138,658
Distribution	13,991,997	14,089,862	13,002,157
Consumer accounts	6,073,710	6,117,625	5,887,713
Administrative, general and other	22,888,048	23,623,299	25,036,248
Depreciation and amortization	36,233,414	35,652,086	40,179,181
Total operating expenses	171,140,389	188,791,558	252,972,879
Interest expense:
Long-term debt and other	21,856,095	22,194,290	23,264,041
Charged to construction	(454,798)	(379,845)	(463,335)
Interest expense, net	21,401,297	21,814,445	22,800,706
Net operating margins	5,205,893	5,815,149	5,544,928
Nonoperating margins:
Interest income	425,173	296,788	566,639
Allowance for funds used during construction	188,111	142,881	163,151
Capital credits, patronage dividends and other	(5,321)	248,034	240,827
Total nonoperating margins	607,963	687,703	970,617
Assignable margins	$ 5,813,856	$ 6,502,852	$ 6,515,545