Condensed Statements of Revenues and Expenses (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Operating revenues:
Sales to Members	$ 310,483	$ 327,776	$ 605,713	$ 597,224
Sales to non-Members	37,220	52,027	61,214	52,353
Total operating revenues	347,703	379,803	666,927	649,577
Operating expenses:
Fuel	136,349	161,355	243,169	233,804
Production	89,844	89,866	188,343	179,055
Depreciation and amortization	40,556	50,927	85,100	85,332
Purchased power	14,660	13,600	29,183	25,155
Accretion	4,859	4,565	9,716	9,125
Deferral of Hawk Road and Smith Energy Facilities effect on net margin	(2,484)	(2,753)	(14,559)	(11,072)
Total operating expenses	283,784	317,560	540,952	521,399
Operating margin	63,919	62,243	125,975	128,178
Other income:
Investment income	7,760	6,926	16,015	14,320
Other	3,156	3,416	6,899	6,782
Total other income	10,916	10,342	22,914	21,102
Interest charges:
Interest expense	78,839	72,279	154,846	142,945
Allowance for debt funds used during construction	(20,017)	(17,753)	(40,437)	(32,981)
Amortization of debt discount and expense	5,135	5,341	10,082	10,488
Net interest charges	63,957	59,867	124,491	120,452
Net margin	$ 10,878	$ 12,718	$ 24,398	$ 28,828