Consolidated Statements of Operations - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Operating Revenues
Other	$ 12,300	$ 20,856
Total revenues	318,508	338,429
Operating expenses
Purchased power	83,458	76,419
Fuel	51,940	60,813
Production	50,795	49,561
Transmission	40,064	33,800
General and administrative	7,728	7,180
Depreciation, amortization, and depletion	40,088	46,672
Coal mining		8,176
Other	4,136	4,790
Operating expenses	278,209	287,411
Operating margins	40,299	51,018
Other income (expense)
Interest	1,203	1,085
Capital credits from cooperatives	4,055	4,246
Membership withdrawal		2,500
Other, net	1,204	1,020
Total other income	6,462	8,851
Interest expense, net of amounts capitalized	38,021	36,349
Income tax benefit	(151)	(302)
Net margins including noncontrolling interest	8,891	23,822
Net income attributable to noncontrolling interest	(797)	(296)
Net margins attributable to the Association	8,094	23,526
Member electric sales
Operating Revenues
Operating revenue	289,346	282,415
Non-member electric sales
Operating Revenues
Operating revenue	$ 16,862	$ 35,158