Consolidated Statements of Cash Flows (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2012	Mar. 31, 2011
Cash flows from operating activities:
Net income	$ 114	$ 214
Less: Loss from discontinued operations	(1)	(2)
Income from continuing operations	115	216
Adjustments to reconcile to net cash provided by operating activities:
Depreciation, decommissioning and amortization	456	417
Regulatory impacts of net nuclear decommissioning trust earnings	77	41
Other amortization	26	37
Asset impairments and other	15	0
Stock-based compensation	8	7
Equity in loss from unconsolidated affiliates	1	5
Distributions from unconsolidated affiliates	0	5
Deferred income taxes and investment tax credits	(22)	226
Income from leveraged leases	(1)	(1)
Proceeds from U.S. treasury grants	29	0
Changes in operating assets and liabilities:
Receivables	118	128
Inventory	44	(18)
Margin and collateral deposits - net of collateral received	(36)	15
Prepaid taxes	(33)	(143)
Other current assets	22	(6)
Rent payments in excess of levelized rent expense	(38)	(32)
Accounts payable	(78)	(49)
Accrued taxes	322	1
Other current liabilities	(426)	(207)
Derivative assets and liabilities - net	295	106
Regulatory assets and liabilities - net	(254)	(42)
Other assets	(7)	(7)
Other liabilities	45	21
Operating cash flows from discontinued operations	(1)	(2)
Net cash provided by operating activities	677	718
Cash flows from financing activities:
Long-term debt issued	449	82
Long-term debt issuance costs	(8)	(1)
Long-term debt repaid	(9)	(9)
Preference stock issued - net	345	123
Short-term debt financing - net	(86)	294
Settlements of stock-based compensation - net	(28)	(7)
Cash contributions from noncontrolling interests	238	0
Dividends and distributions to noncontrolling interests	(14)	(13)
Dividends paid	(106)	(104)
Net cash provided by financing activities	781	365
Cash flows from investing activities:
Capital expenditures	(1,276)	(1,133)
Proceeds from sale of nuclear decommissioning trust investments	602	622
Purchases of nuclear decommissioning trust investments and other	(684)	(669)
Proceeds from partnerships and unconsolidated subsidiaries, net of investment	1	5
Investments in other assets	(87)	1
Net cash used by investing activities	(1,444)	(1,174)
Net increase (decrease) in cash and cash equivalents	14	(91)
Cash and cash equivalents, beginning of period	1,469	1,389
Cash and cash equivalents, end of period	$ 1,483	$ 1,298