CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Cash flows from operating activities:
Net margin	$ 37,737	$ 33,733	$ 26,390
Adjustments to reconcile net margin to net cash provided by operating activities:
Depreciation and amortization, including nuclear fuel	321,715	250,723	225,423
Accretion cost	18,249	17,131	18,261
Amortization of deferred gains	(5,660)	(5,660)	(5,660)
Allowance for equity funds used during construction	(2,904)	(2,417)	(2,394)
Deferred outage costs	(56,358)	(25,911)	(35,464)
Deferral of Hawk Road and Murray Energy facilities effect on net margin	(9,681)	13,849	8,107
Loss (gain) on sale of investments	(14,915)	(14,239)	6,938
Regulatory deferral of costs associated with nuclear decommissioning	5,089	5,480	(18,465)
Other	(10,598)	(9,022)	(5,021)
Change in operating assets and liabilities:
Receivables	(8,456)	(7,299)	1,064
Inventories	(40,774)	38,022	(29,703)
Prepayments and other current assets	(2,146)	(4,023)	(3,480)
Accounts payable	8,617	(729)	(1,876)
Accrued interest	14,671	25,488	16,408
Accrued and withheld taxes	(6,362)	2,307	5,996
Other current liabilities	542	791	6,639
Member power bill prepayments	(10,177)	(88,018)	195,514
Total adjustments	200,852	196,473	382,287
Net cash provided by operating activities	238,589	230,206	408,677
Cash flows from investing activities:
Property additions	(839,503)	(669,206)	(627,148)
Plant acquisitions	(530,293)		(274,251)
Activity in nuclear decommissioning trust fund - Purchases	(1,068,979)	(608,542)	(635,081)
Activity in nuclear decommissioning trust fund - Proceeds	1,063,277	603,600	630,055
(Increase) decrease in restricted cash and cash equivalents	(37,383)	16,105	(12,150)
Increase in restricted short-term investments	(9,390)	(16,696)	(80,590)
Decrease (increase) in investment in associated organizations	472	(599)	(9,033)
Activity in other long-term investments - Purchases	(2,469)	(6,822)	(1,963)
Activity in other long-term investments - Proceeds	1,100	18,524	2,600
Activity on interest rate options - Purchases	(100,000)
Activity on interest rate options - Collateral received	43,070
Other	(10,726)	3,421	(3,944)
Net cash used in investing activities	(1,490,824)	(660,215)	(1,011,505)
Cash flows from financing activities:
Long-term debt proceeds	1,163,593	740,124	992,246
Long-term debt payments	(288,722)	(240,185)	(110,905)
Increase in short-term borrowings	155,135	22,325	143,634
Other	(6,312)	888	(10,737)
Net cash provided by financing activities	1,023,694	523,152	1,014,238
Net (decrease) increase in cash and cash equivalents	(228,541)	93,143	411,410
Cash and cash equivalents at beginning of period	672,212	579,069	167,659
Cash and cash equivalents at end of period	443,671	672,212	579,069
Cash paid for -
Interest (net of amounts capitalized)	196,629	187,958	193,897
Supplemental disclosure of non-cash investing and financing activities:
Change in plant expenditures included in accounts payable	$ (7,848)	$ 138,898	$ (969)