Consolidated Statements of Cash Flows - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014
Cash flows from operating activities:
Net margin	$ 26,221	$ 36,419
Adjustments to reconcile net margin to net cash provided by operating activities:
Depreciation and amortization, including nuclear fuel	156,416	153,759
Accretion cost	12,859	12,126
Amortization of deferred gains	(894)	(894)
Allowance for equity funds used during construction	(342)	(731)
Deferred outage costs	(18,274)	(31,411)
Deferral of Hawk Road and Smith Energy Facilities effect on net margin	(41,689)	(20,136)
Gain on sale of investments	(32,470)	(8,961)
Regulatory deferral of costs associated with nuclear decommissioning	25,781	1,571
Other	13,216	6,816
Change in operating assets and liabilities:
Receivables	(11,171)	(21,180)
Inventories	2,857	32,455
Prepayments and other current assets	(10,664)	1,209
Accounts payable	(45,059)	(45,456)
Accrued interest	(49)	183
Accrued taxes	820	(3,978)
Other current liabilities	(8,681)	(2,479)
Member power bill prepayments	(11,033)	14,475
Total adjustments	31,623	87,368
Net cash provided by operating activities	57,844	123,787
Cash flows from investing activities:
Property additions	(256,038)	(249,317)
Activity in nuclear decommissioning trust fund - Purchases	(281,938)	(188,815)
Activity in nuclear decommissioning trust fund - Proceeds	279,751	186,165
Decrease in restricted cash and investments	41,855	32,209
Increase in restricted short-term investments	(5,524)	(21,173)
Activity in other long-term investments - Purchases	(23,746)	(28,690)
Activity in other long-term investments - Proceeds	24,973	30,385
Activity on interest rate options - Collateral returned		(73,850)
Activity on interest rate options - Collateral received		41,640
Other	(8,450)	473
Net cash used in investing activities	(229,117)	(270,973)
Cash flows from financing activities:
Long-term debt proceeds	271,892	993,707
Long-term debt payments	(76,418)	(333,127)
Increase (decrease) in short-term borrowings, net	27,375	(548,494)
Other	(2,190)	(43,227)
Net cash provided by financing activities	220,659	68,859
Net increase (decrease) in cash and cash equivalents	49,386	(78,327)
Cash and cash equivalents at beginning of period	237,391	408,193
Cash and cash equivalents at end of period	286,777	329,866
Cash paid for -
Interest (net of amounts capitalized)	127,026	115,231
Supplemental disclosure of non-cash investing and financing activities:
Change in plant expenditures included in accounts payable	$ (8,454)	$ 22,904