Consolidated Statements of Cash Flows (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Operating Activities
Net Income	$ 486	$ 437	$ 441
Adjustments to reconcile net income to net cash from operating activities:
Depreciation, depletion and amortization	822	813	849
Deferred income taxes	(52)	231	322
Asset (gains), losses and reserves, net	(2)	13	(6)
Changes in assets and liabilities, exclusive of changes shown separately (Note 17)	258	(141)	(253)
Net cash from operating activities	1,512	1,353	1,353
Investing Activities
Plant and equipment expenditures	(1,230)	(1,202)	(864)
Restricted cash for debt redemption, principally Securitization	5	(3)	(25)
Notes receivable from affiliate	26	77	(21)
Proceeds from sale of nuclear decommissioning trust fund assets	97	80	377
Investment in nuclear decommissioning trust funds	(102)	(97)	(410)
Other investments	(26)	(32)	(60)
Net cash used for investing activities	(1,230)	(1,177)	(1,003)
Financing Activities
Issuance of long-term debt	496	609	614
Redemption of long-term debt	(587)	(554)	(652)
Short-term borrowings, net	130	0	0
Short-term borrowings from affiliate	16	64	0
Dividends on common stock	(317)	(305)	(305)
Other	(3)	(7)	(11)
Net cash used for financing activities	(265)	(193)	(354)
Net Increase (Decrease) in Cash and Cash Equivalents	17	(17)	(4)
Cash and Cash Equivalents at Beginning of Period	13	30	34
Cash and Cash Equivalents at End of Period	$ 30	$ 13	$ 30