Accumulated Other Comprehensive Income (Loss), Net of Tax (Reclassifications of AOCI) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Gains (Losses) on Cash Flow Hedges	$ 2,310	$ 2,098	$ 5,096	$ 4,973
Tax Expense (Benefit)	(218)	(146)	(438)	(358)
Net Income (Loss)	333	211	653	704
Interest Expense	101	103	203	204
Income (Loss) from Continuing Operations before Income Taxes	551	357	1,091	1,062
Power [Member]
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Gains (Losses) on Cash Flow Hedges	1,190	985	2,637	2,546
Tax Expense (Benefit)	(139)	(73)	(230)	(241)
Net Income (Loss)	204	104	341	357
Interest Expense	29	32	59	62
Income (Loss) from Continuing Operations before Income Taxes	343	177	571	598
Power [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Tax Expense (Benefit)	5		8
Net Income (Loss)	(7)		(12)
Income (Loss) from Continuing Operations before Income Taxes	(12)		(20)
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	2		8
Tax Expense (Benefit)	(1)		(3)
Net Income (Loss)	1		5
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		4
Amortization of Prior Service Cost, Tax	(1)		(2)
Amortization of Prior Service Cost, After-Tax	1		2
Amortization of Actuarial Loss, Pre-Tax	(16)		(32)
Amortization of Actuarial Loss, Tax	7		13
Amortization of Actuarial Loss, After-Tax	(9)		(19)
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		4
Realized Gain (Loss) on NDT Fund, Tax	(1)		(2)
Realized Gain (Loss) on NDT Fund. After-Tax	1		2
Other-Than-Temporary Impairments on NDT Fund, Pre-Tax	(2)		(4)
Other-Than-Temporary Impairments on NDT Fund, Tax	1		2
Other-Than-Temporary Impairments on NDT Fund, After-Tax	(1)		(2)
PSEG [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Tax Expense (Benefit)	6		11
Net Income (Loss)	(9)		(15)
Income (Loss) from Continuing Operations before Income Taxes	(15)		(26)
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	2		8
Tax Expense (Benefit)	(1)		(3)
Net Income (Loss)	1		5
PSEG [Member] | Interest Rate Swap [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Tax Expense (Benefit)	0		0
Interest Expense	(1)		(1)
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	1		5
Amortization of Prior Service Cost, Tax	0		(2)
Amortization of Prior Service Cost, After-Tax	1		3
Amortization of Actuarial Loss, Pre-Tax	(17)		(38)
Amortization of Actuarial Loss, Tax	7		16
Amortization of Actuarial Loss, After-Tax	(10)		(22)
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		4
Realized Gain (Loss) on NDT Fund, Tax	(1)		(2)
Realized Gain (Loss) on NDT Fund. After-Tax	1		2
Other-Than-Temporary Impairments on NDT Fund, Pre-Tax	(2)		(4)
Other-Than-Temporary Impairments on NDT Fund, Tax	1		2
Other-Than-Temporary Impairments on NDT Fund, After-Tax	$ (1)		$ (2)