Employee Benefit Plans (Net Periodic Benefit (Credit) Cost and Amounts Recognized in Other Comprehensive Income and Regulatory Assets and Liabilities) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2011		Dec. 31, 2010		Dec. 31, 2009
Expected return on plan assets	$ (519)		$ (479)
Pension Benefits [Member]
Service cost	108		102		106
Interest cost	258		266		250
Expected return on plan assets	(440)		(410)		(405)
Amortization of prior service (credit) cost	3		3		4
Amortization of net actuarial loss	96		59		38
Settlements and curtailments	0	[1]	136	[1]	3	[1]
Special termination benefits	0	[2]	10	[2]	0	[2]
Plan amendments	0		0		1
Net periodic benefit cost (credit)	25		166		(3)
Changes in plan assets and benefit obligations recognized in other comprehensive income and regulatory assets and liabilities:
Current year net actuarial (gain) loss	534		95		(174)
Prior service (credit) cost	0		1		0
Settlements and curtailments	0	[1]	(50)	[1]	(2)	[1]
Amortization of net actuarial loss	(96)		(59)		(38)
Amortization of prior service credit (cost)	(3)		(3)		(4)
Total recognized in other comprehensive income and regulatory assets and liabilities	435		(16)		(218)
Significant assumptions used to determine periodic cost:
Discount rate	5.90%		6.60%		6.60%
Expected long-term rate of return on plan assets	8.50%		8.50%		8.50%
Weighted average rate of increase for compensation	4.61%		4.76%		4.79%
Other Postretirement Benefits [Member]
Service cost	48		56		60
Interest cost	94		101		100
Expected return on plan assets	(79)		(69)		(57)
Amortization of prior service (credit) cost	(13)		(7)		(7)
Amortization of net actuarial loss	12		12		30
Settlements and curtailments	1	[1]	37	[1]	0	[1]
Special termination benefits	0	[2]	1	[2]	0	[2]
Plan amendments	0		0		0
Net periodic benefit cost (credit)	63		131		126
Changes in plan assets and benefit obligations recognized in other comprehensive income and regulatory assets and liabilities:
Current year net actuarial (gain) loss	(157)		13		(172)
Prior service (credit) cost	(70)		0		(1)
Settlements and curtailments	(1)	[1]	(1)	[1]	0	[1]
Amortization of net actuarial loss	(12)		(12)		(30)
Amortization of prior service credit (cost)	13		7		7
Total recognized in other comprehensive income and regulatory assets and liabilities	$ (227)		$ 7		$ (196)
Significant assumptions used to determine periodic cost:
Discount rate	5.90%		6.60%		6.60%
Expected long-term rate of return on plan assets	7.75%		7.75%		7.75%
Weighted average rate of increase for compensation	4.62%		4.79%		4.78%
Healthcare cost trend rate	7.00%		7.00%		8.00%
Rate to which the cost trend rate is assumed to decline	4.60%		4.60%		4.90%
Year that the rate reaches the ultimate trend rate	2060		2060		2060

[1] 2010 amounts relate to the sales of Peoples and Dominion's Appalachian E&P operations and a workforce reduction program.

[2] Represents a one-time special termination benefit for certain employees in connection with a workforce reduction program.