CONDENSED CONSOLIDATED BALANCE SHEETS (Unaudited) (USD $) In Millions, unless otherwise specified	Dec. 31, 2011	Dec. 31, 2010
Current Assets:
Cash and cash equivalents ($198 and $220 related to VIEs at December 31, 2010 and 2011, respectively)	$ 220	$ 198
Accounts and notes receivable, net ($49 and $52 related to VIEs at December 31, 2010 and 2011, respectively)	201	203
Accounts and notes receivable—affiliated companies	1,027	919
Accrued unbilled revenues	72	70
Inventory	80	71
Taxes receivable	2	63
Deferred tax asset	3	3
Other ($39 and $42 related to VIEs at December 31, 2010 and 2011, respectively)	65	62
Total current assets	1,670	1,589
Property, Plant and Equipment [Abstract]
Property, Plant and Equipment, net	5,043	4,781
Other Assets:
Regulatory assets ($2,597 and $2,289 related to VIEs at December 31, 2010 and 2011, respectively)	3,726	2,675
Notes receivable—affiliated companies	750	750
Other	35	37
Total other assets	4,511	3,462
Total Assets	11,224	9,832
Current Liabilities:
Current portion of VIE transition and system restoration bonds long-term debt	307	283
Current portion of other long-term debt	46	0
Accounts payable	113	76
Accounts and notes payable—affiliated companies	32	36
Taxes accrued	101	92
Interest accrued	96	101
Other	98	74
Total current liabilities	793	662
Other Liabilities:
Accumulated deferred income taxes, net	2,113	1,428
Benefit obligations	252	215
Regulatory liabilities	441	417
Notes payable—affiliated companies	151	151
Other	78	297
Total other liabilities	3,035	2,508
Long-Term Debt:
VIE transition and system restoration bonds	2,215	2,522
Other	2,047	2,092
Total long-term debt	4,262	4,614
Commitments And Contingencies (Note 10)
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest [Abstract]
Member’s Equity	3,134	2,048
Total Liabilities and Member’s Equity	$ 11,224	$ 9,832