Consolidated Statements of Cash Flows (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Operating Activities
Net income	$ 437	$ 441	$ 376
Adjustments to reconcile net income to net cash from operating activities:
Depreciation and amortization	813	849	844
Deferred income taxes	231	322	15
Asset (gains) losses and reserves, net	13	(6)	(2)
Changes in assets and liabilities, exclusive of changes shown separately (Note 17)	(141)	(253)	(39)
Net cash from operating activities	1,353	1,353	1,194
Investing Activities
Plant and equipment expenditures	(1,202)	(864)	(793)
Restricted cash	(3)	(25)	5
Notes receivable from affiliate	77	(21)	(42)
Proceeds from sale of nuclear decommissioning trust fund assets	80	377	295
Investment in nuclear decommissioning trust funds	(97)	(410)	(315)
Other investments	(32)	(60)	(46)
Net cash used for investing activities	(1,177)	(1,003)	(896)
Financing Activities
Issuance of long-term debt	609	614	129
Redemption of long-term debt	(554)	(652)	(278)
Short-term borrowings, net	0	0	(75)
Short-term borrowings from affiliate	64	0	0
Capital contribution by parent company	0	0	250
Dividends on common stock	(305)	(305)	(305)
Other	(7)	(11)	(15)
Net cash used for financing activities	(193)	(354)	(294)
Net Increase (Decrease) in Cash and Cash Equivalents	(17)	(4)	4
Cash and Cash Equivalents at Beginning of Period	30	34	30
Cash and Cash Equivalents at End of Period	$ 13	$ 30	$ 34