Accumulated Other Comprehensive Income (Loss), Net of Tax (Reclassifications of AOCI) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Gains (Losses) on Cash Flow Hedges	$ 2,786	$ 2,875
Tax Expense (Benefit)	(220)	(212)
Net Income (Loss)	320	493
Income (Loss) from Continuing Operations before Income Taxes	540	705
Power [Member]
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Gains (Losses) on Cash Flow Hedges	1,447	1,561
Tax Expense (Benefit)	(91)	(168)
Net Income (Loss)	137	253
Income (Loss) from Continuing Operations before Income Taxes	228	421
Power [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Tax Expense (Benefit)	3
Net Income (Loss)	(5)
Income (Loss) from Continuing Operations before Income Taxes	(8)
Power [Member] | Derivative Contracts [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Gains (Losses) on Cash Flow Hedges	6
Tax Expense (Benefit)	(2)
Net Income (Loss)	4
Power [Member] | Pension and OPEB Plans [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Amortization of Prior Service Cost, Pre-Tax	2
Amortization of Prior Service Cost, Tax	(1)
Amortization of Prior Service Cost, After-Tax	1
Amortization of Actuarial Loss, Pre-Tax	(16)
Amortization of Actuarial Loss, Tax	6
Amortization of Actuarial Loss, After-Tax	(10)
Power [Member] | Available-for-Sale Securities [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Realized Gain (Loss) on NDT Fund, Pre-Tax	2
Realized Gain (Loss) on NDT Fund, Tax	(1)
Realized Gain (Loss) on NDT Fund. After-Tax	1
Other-Than-Temporary Impairments on NDT Fund, Pre-Tax	(2)
Other-Than-Temporary Impairments on NDT Fund, Tax	1
Other-Than-Temporary Impairments on NDT Fund, After-Tax	(1)
PSEG [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Tax Expense (Benefit)	5
Net Income (Loss)	(6)
Income (Loss) from Continuing Operations before Income Taxes	(11)
PSEG [Member] | Derivative Contracts [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Gains (Losses) on Cash Flow Hedges	6
Tax Expense (Benefit)	(2)
Net Income (Loss)	4
PSEG [Member] | Pension and OPEB Plans [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Amortization of Prior Service Cost, Pre-Tax	4
Amortization of Prior Service Cost, Tax	(2)
Amortization of Prior Service Cost, After-Tax	2
Amortization of Actuarial Loss, Pre-Tax	(21)
Amortization of Actuarial Loss, Tax	9
Amortization of Actuarial Loss, After-Tax	(12)
PSEG [Member] | Available-for-Sale Securities [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Realized Gain (Loss) on NDT Fund, Pre-Tax	2
Realized Gain (Loss) on NDT Fund, Tax	(1)
Realized Gain (Loss) on NDT Fund. After-Tax	1
Other-Than-Temporary Impairments on NDT Fund, Pre-Tax	(2)
Other-Than-Temporary Impairments on NDT Fund, Tax	1
Other-Than-Temporary Impairments on NDT Fund, After-Tax	$ (1)