Income Taxes (Narrative) (Details) (USD $) In Millions, unless otherwise specified	0 Months Ended			3 Months Ended	16 Months Ended
	Jun. 26, 2009	Sep. 15, 2008	Dec. 17, 2007	Mar. 31, 2012	Dec. 31, 2011
Component of Other Income, Nonoperating [Line Items]
Average tax benefits recognition period, years				20
Amount of unrecognized tax benefits that would affect the effective tax rate				$ 319
PSE And G [Member]
Component of Other Income, Nonoperating [Line Items]
Investment tax credit				7
Unrecognized tax benefit decrease on settlement with IRS				30
PSEG [Member]
Component of Other Income, Nonoperating [Line Items]
Bonus depreciation for tax purposes				50.00%	100.00%
Average tax benefits recognition period, years				10
Increase in unrecognized tax benefits reasonably likely to increase or decrease within one year				559	172
Tax benefits from IRS settlement in leasing issue				387
Impact Of Unrecognized Tax				240
Interest and Penalties for decrease in uncertain tax position				352
Tax deposit	140	80	100
Unrecognized tax benefit decrease on settlement with IRS				70
Power [Member]
Component of Other Income, Nonoperating [Line Items]
Unrecognized tax benefit decrease on settlement with IRS				$ 1