Consolidated Statements of Cash Flows (USD $) In Millions, unless otherwise specified	6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011
Cash flows from operating activities:
Net income	$ 215	$ 405
Less: Loss from discontinued operations	(1)	(3)
Income from continuing operations	216	408
Adjustments to reconcile to net cash provided by operating activities:
Depreciation, decommissioning and amortization	924	852
Regulatory impacts of net nuclear decommissioning trust earnings	114	75
Other amortization	49	75
Asset impairments and other	26	7
Stock-based compensation	18	15
Equity in income from unconsolidated affiliates	(17)	(12)
Distributions from unconsolidated affiliates	6	15
Deferred income taxes and investment tax credits	(93)	223
Income from leveraged leases	(3)	(3)
Proceeds from U.S. treasury grants	29	0
Changes in operating assets and liabilities:
Receivables	10	64
Inventory	57	(21)
Margin and collateral deposits - net of collateral received	(20)	1
Prepaid taxes	(3)	34
Other current assets	(217)	(189)
Rent payments in excess of levelized rent expense	(38)	(101)
Accounts payable	0	66
Accrued taxes	(15)	(19)
Other current liabilities	(115)	(212)
Derivative assets and liabilities - net	(92)	303
Regulatory assets and liabilities - net	252	(260)
Other assets	(7)	(38)
Other liabilities	80	(58)
Operating cash flows from discontinued operations	(1)	(3)
Net cash provided by operating activities	1,160	1,222
Cash flows from financing activities:
Long-term debt issued	495	592
Long-term debt issuance costs	(11)	(5)
Long-term debt repaid	(29)	(30)
Bonds purchased	0	(56)
Preference stock issued - net	805	123
Preference stock redeemed	(75)	0
Short-term debt financing - net	(112)	292
Settlements of stock-based compensation - net	(41)	(13)
Cash contributions from noncontrolling interests	238	0
Dividends and distributions to noncontrolling interests	(36)	(28)
Dividends paid	(212)	(209)
Net cash provided by financing activities	1,022	666
Cash flows from investing activities:
Capital expenditures	(2,291)	(2,256)
Proceeds from sale of nuclear decommissioning trust investments	1,097	1,146
Purchases of nuclear decommissioning trust investments and other	(1,222)	(1,230)
Proceeds from partnerships and unconsolidated subsidiaries, net of investment	5	5
Restricted deposits and restricted cash and cash equivalents	(69)	19
Customer advances for construction and other investments	4	(16)
Net cash used by investing activities	(2,476)	(2,332)
Net decrease in cash and cash equivalents	(294)	(444)
Cash and cash equivalents, beginning of period	1,469	1,389
Cash and cash equivalents, end of period	$ 1,175	$ 945