Guarantees Of Debt (Schedule Of Financial Statements Of Guarantors) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2012	Mar. 31, 2011	Dec. 31, 2011
Operating Revenues	$ 2,875	$ 3,354
Operating Expenses	2,092	2,498
Operating Income (Loss)	783	856
Equity Earnings (Losses) of Subsidiaries	0	3
Other Income	44	76
Other Deductions	(16)	(13)
Other-Than-Temporary Impairments	(5)	(4)
Interest Expense	101	127
Income Tax Benefit (Expense)	212	329
Income (Loss) on Discontinued Operations, net of tax	0	64
Net Income (Loss)	493	526
Net Cash Provided By (Used In) Operating Activities	1,088	1,042
Net Cash Provided By (Used In) Investing Activities	(706)	(155)
Net Cash Provided By (Used In) Financing Activities	(285)	(267)
Current Assets	3,961		3,911
Property, Plant and Equipment, net	18,233		17,849
Noncurrent Assets	7,808		8,061
Total Assets	30,002		29,821
Current Liabilities	3,108		2,957
Noncurrent Liabilities	9,009		9,131
Long-Term Debt	7,259		7,461
Member's Equity	10,626		10,272
Total Liabilities and Member's Equity	30,002		29,821
Power [Member]
Operating Revenues	1,561	1,967
Operating Expenses	1,120	1,466
Operating Income (Loss)	441	501
Other Income	30	70
Other Deductions	(15)	(12)
Other-Than-Temporary Impairments	(5)	(2)
Interest Expense	30	51
Income Tax Benefit (Expense)	168	208
Income (Loss) on Discontinued Operations, net of tax	0	64
Net Income (Loss)	253	362
Net Cash Provided By (Used In) Operating Activities	731	903
Net Cash Provided By (Used In) Investing Activities	(365)	(729)
Net Cash Provided By (Used In) Financing Activities	(373)	(175)
Current Assets	2,505		2,687
Property, Plant and Equipment, net	6,795		6,731
Noncurrent Assets	1,789		1,669
Total Assets	11,089		11,087
Current Liabilities	797		902
Noncurrent Liabilities	2,165		2,056
Long-Term Debt	2,685		2,685
Member's Equity	5,442		5,444
Total Liabilities and Member's Equity	11,089		11,087
Power Senior Notes [Member]
Operating Revenues	1,561	1,967
Operating Expenses	1,120	1,466
Operating Income (Loss)	441	501
Equity Earnings (Losses) of Subsidiaries	0	0
Other Income	30	70
Other Deductions	(15)	(12)
Other-Than-Temporary Impairments	(5)	(2)
Interest Expense	(30)	(51)
Income Tax Benefit (Expense)	(168)	(208)
Income (Loss) on Discontinued Operations, net of tax		64
Net Income (Loss)	253	362
Net Cash Provided By (Used In) Operating Activities	731	903
Net Cash Provided By (Used In) Investing Activities	(365)	(729)
Net Cash Provided By (Used In) Financing Activities	(373)	(175)
Current Assets	2,505		2,687
Property, Plant and Equipment, net	6,795		6,731
Investment in Subsidiaries	0		0
Noncurrent Assets	1,789		1,669
Total Assets	11,089		11,087
Current Liabilities	797		902
Noncurrent Liabilities	2,165		2,056
Long-Term Debt	2,685		2,685
Member's Equity	5,442		5,444
Total Liabilities and Member's Equity	11,089		11,087
Power Senior Notes [Member] | Power [Member]
Operating Revenues	0	0
Operating Expenses	(2)	2
Operating Income (Loss)	2	(2)
Equity Earnings (Losses) of Subsidiaries	260	382
Other Income	13	10
Other Deductions	(7)	(3)
Other-Than-Temporary Impairments	0	(1)
Interest Expense	(29)	(45)
Income Tax Benefit (Expense)	14	21
Income (Loss) on Discontinued Operations, net of tax		0
Net Income (Loss)	253	362
Net Cash Provided By (Used In) Operating Activities	124	350
Net Cash Provided By (Used In) Investing Activities	242	(175)
Net Cash Provided By (Used In) Financing Activities	(366)	(175)
Current Assets	4,137		4,311
Property, Plant and Equipment, net	66		66
Investment in Subsidiaries	4,283		4,185
Noncurrent Assets	197		179
Total Assets	8,683		8,741
Current Liabilities	106		172
Noncurrent Liabilities	450		440
Long-Term Debt	2,685		2,685
Member's Equity	5,442		5,444
Total Liabilities and Member's Equity	8,683		8,741
Power Senior Notes [Member] | Guarantor Subsidiaries [Member]
Operating Revenues	1,873	2,278
Operating Expenses	1,433	1,774
Operating Income (Loss)	440	504
Equity Earnings (Losses) of Subsidiaries	(3)	60
Other Income	31	71
Other Deductions	(8)	(9)
Other-Than-Temporary Impairments	(5)	(1)
Interest Expense	(10)	(11)
Income Tax Benefit (Expense)	(185)	(232)
Income (Loss) on Discontinued Operations, net of tax		0
Net Income (Loss)	260	382
Net Cash Provided By (Used In) Operating Activities	723	1,202
Net Cash Provided By (Used In) Investing Activities	(656)	(777)
Net Cash Provided By (Used In) Financing Activities	(73)	(426)
Current Assets	7,628		7,248
Property, Plant and Equipment, net	5,773		5,715
Investment in Subsidiaries	801		804
Noncurrent Assets	1,661		1,557
Total Assets	15,863		15,324
Current Liabilities	9,885		9,549
Noncurrent Liabilities	1,694		1,589
Long-Term Debt	0		0
Member's Equity	4,284		4,186
Total Liabilities and Member's Equity	15,863		15,324
Power Senior Notes [Member] | Other Subsidiaries [Member]
Operating Revenues	26	50
Operating Expenses	27	52
Operating Income (Loss)	(1)	(2)
Equity Earnings (Losses) of Subsidiaries	0	0
Other Income	0	0
Other Deductions	0	0
Other-Than-Temporary Impairments	0	0
Interest Expense	(4)	(5)
Income Tax Benefit (Expense)	2	3
Income (Loss) on Discontinued Operations, net of tax		64
Net Income (Loss)	(3)	60
Net Cash Provided By (Used In) Operating Activities	2	(189)
Net Cash Provided By (Used In) Investing Activities	(13)	336
Net Cash Provided By (Used In) Financing Activities	10	(147)
Current Assets	953		951
Property, Plant and Equipment, net	956		950
Investment in Subsidiaries	0		0
Noncurrent Assets	59		51
Total Assets	1,968		1,952
Current Liabilities	1,021		1,003
Noncurrent Liabilities	145		145
Long-Term Debt	0		0
Member's Equity	802		804
Total Liabilities and Member's Equity	1,968		1,952
Power Senior Notes [Member] | Consolidating Adjustments [Member]
Operating Revenues	(338)	(361)
Operating Expenses	(338)	(362)
Operating Income (Loss)	0	1
Equity Earnings (Losses) of Subsidiaries	(257)	(442)
Other Income	(14)	(11)
Other Deductions	0	0
Other-Than-Temporary Impairments	0	0
Interest Expense	13	10
Income Tax Benefit (Expense)	1	0
Income (Loss) on Discontinued Operations, net of tax		0
Net Income (Loss)	(257)	(442)
Net Cash Provided By (Used In) Operating Activities	(118)	(460)
Net Cash Provided By (Used In) Investing Activities	62	(113)
Net Cash Provided By (Used In) Financing Activities	56	573
Current Assets	(10,213)		(9,823)
Property, Plant and Equipment, net	0		0
Investment in Subsidiaries	(5,084)		(4,989)
Noncurrent Assets	(128)		(118)
Total Assets	(15,425)		(14,930)
Current Liabilities	(10,215)		(9,822)
Noncurrent Liabilities	(124)		(118)
Long-Term Debt	0		0
Member's Equity	(5,086)		(4,990)
Total Liabilities and Member's Equity	$ (15,425)		$ (14,930)