Fair Value Measurements (PSEG's, Power's And PSE&G's Respective Assets And (Liabilities) Measured At Fair Value On A Recurring Basis) (Detail) (USD $) In Millions, unless otherwise specified	Jun. 30, 2012		Dec. 31, 2011
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total Mark-to-Market Derivative Assets	$ 298		$ 262
Total Mark-to-Market Derivative (Liabilities)	200		157
Power [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total Mark-to-Market Derivative Assets	186		194
Total Mark-to-Market Derivative (Liabilities)	96		148
Total Estimate Of Fair Value [Member] | PSEG [Member] | Energy-Related Contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total Mark-to-Market Derivative Assets	232	[1]	198	[1]
Total Mark-to-Market Derivative (Liabilities)	(200)	[1]	(155)	[1]
Total Estimate Of Fair Value [Member] | PSEG [Member] | Interest Rate Swap [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total Mark-to-Market Derivative Assets	66	[2]	64	[2]
Total Mark-to-Market Derivative (Liabilities)			(2)	[2]
Total Estimate Of Fair Value [Member] | PSEG [Member] | Equity Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	728	[3]	685	[3]
Total Estimate Of Fair Value [Member] | PSEG [Member] | Government Obligations [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	306	[3]	359	[3]
Total Estimate Of Fair Value [Member] | PSEG [Member] | Other Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	320	[3]	281	[3]
Total Estimate Of Fair Value [Member] | PSEG [Member] | Other Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	62	[3]	24	[3]
Total Estimate Of Fair Value [Member] | PSEG [Member] | Rabbi Trusts - Mutual Funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments			172	[3]
Total Estimate Of Fair Value [Member] | PSEG [Member] | Non-Recourse Debt [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total Mark-to-Market Derivative (Liabilities)			(50)	[4]
Total Estimate Of Fair Value [Member] | PSEG [Member] | Rabbi Trust - Equity Securities-Mutual Funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	16	[3]
Total Estimate Of Fair Value [Member] | PSEG [Member] | Rabbi Trust - Debt Securities-Govt Obligations [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	116	[3]
Total Estimate Of Fair Value [Member] | PSEG [Member] | Rabbi Trust - Debt Securities-Other [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	44	[3]
Total Estimate Of Fair Value [Member] | PSEG [Member] | Rabbi Trust - Other Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	3	[3]
Total Estimate Of Fair Value [Member] | Power [Member] | Energy-Related Contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total Mark-to-Market Derivative Assets	186	[1]	194	[1]
Total Mark-to-Market Derivative (Liabilities)	(96)	[1]	(148)	[1]
Total Estimate Of Fair Value [Member] | Power [Member] | Equity Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	728	[3]	685	[3]
Total Estimate Of Fair Value [Member] | Power [Member] | Government Obligations [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	306	[3]	359	[3]
Total Estimate Of Fair Value [Member] | Power [Member] | Other Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	320	[3]	281	[3]
Total Estimate Of Fair Value [Member] | Power [Member] | Other Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	62	[3]	24	[3]
Total Estimate Of Fair Value [Member] | Power [Member] | Rabbi Trusts - Mutual Funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments			33	[3]
Total Estimate Of Fair Value [Member] | Power [Member] | Rabbi Trust - Equity Securities-Mutual Funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	3	[3]
Total Estimate Of Fair Value [Member] | Power [Member] | Rabbi Trust - Debt Securities-Govt Obligations [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	23	[3]
Total Estimate Of Fair Value [Member] | Power [Member] | Rabbi Trust - Debt Securities-Other [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	8	[3]
Total Estimate Of Fair Value [Member] | Power [Member] | Rabbi Trust - Other Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	1	[3]
Total Estimate Of Fair Value [Member] | PSE And G [Member] | Energy-Related Contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total Mark-to-Market Derivative Assets	46	[1]	4	[1]
Total Mark-to-Market Derivative (Liabilities)	(104)	[1]	(7)	[1]
Total Estimate Of Fair Value [Member] | PSE And G [Member] | Rabbi Trusts - Mutual Funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total Mark-to-Market Derivative Assets			57	[3]
Total Estimate Of Fair Value [Member] | PSE And G [Member] | Rabbi Trust - Equity Securities-Mutual Funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	5	[3]
Total Estimate Of Fair Value [Member] | PSE And G [Member] | Rabbi Trust - Debt Securities-Govt Obligations [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	38	[3]
Total Estimate Of Fair Value [Member] | PSE And G [Member] | Rabbi Trust - Debt Securities-Other [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	15	[3]
Total Estimate Of Fair Value [Member] | PSE And G [Member] | Rabbi Trust - Other Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	1	[3]
Cash Collateral Netting [Member] | PSEG [Member] | Energy-Related Contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total Mark-to-Market Derivative Assets	(83)	[1]	(100)	[1]
Total Mark-to-Market Derivative (Liabilities)	10	[1]	18	[1]
Cash Collateral Netting [Member] | PSEG [Member] | Interest Rate Swap [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total Mark-to-Market Derivative Assets	0	[2]	0	[2]
Total Mark-to-Market Derivative (Liabilities)			0	[2]
Cash Collateral Netting [Member] | PSEG [Member] | Equity Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	0	[3]	0	[3]
Cash Collateral Netting [Member] | PSEG [Member] | Government Obligations [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	0	[3]	0	[3]
Cash Collateral Netting [Member] | PSEG [Member] | Other Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	0	[3]	0	[3]
Cash Collateral Netting [Member] | PSEG [Member] | Other Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	0	[3]	0	[3]
Cash Collateral Netting [Member] | PSEG [Member] | Rabbi Trusts - Mutual Funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments			0	[3]
Cash Collateral Netting [Member] | PSEG [Member] | Non-Recourse Debt [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total Mark-to-Market Derivative (Liabilities)			0	[4]
Cash Collateral Netting [Member] | PSEG [Member] | Rabbi Trust - Equity Securities-Mutual Funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	0	[3]
Cash Collateral Netting [Member] | PSEG [Member] | Rabbi Trust - Debt Securities-Govt Obligations [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	0	[3]
Cash Collateral Netting [Member] | PSEG [Member] | Rabbi Trust - Debt Securities-Other [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	0	[3]
Cash Collateral Netting [Member] | PSEG [Member] | Rabbi Trust - Other Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	0	[3]
Cash Collateral Netting [Member] | Power [Member] | Energy-Related Contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total Mark-to-Market Derivative Assets	(83)	[1]	(100)	[1]
Total Mark-to-Market Derivative (Liabilities)	10	[1]	18	[1]
Cash Collateral Netting [Member] | Power [Member] | Equity Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	0	[3]	0	[3]
Cash Collateral Netting [Member] | Power [Member] | Government Obligations [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	0	[3]	0	[3]
Cash Collateral Netting [Member] | Power [Member] | Other Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	0	[3]	0	[3]
Cash Collateral Netting [Member] | Power [Member] | Other Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	0	[3]	0	[3]
Cash Collateral Netting [Member] | Power [Member] | Rabbi Trusts - Mutual Funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments			0	[3]
Cash Collateral Netting [Member] | Power [Member] | Rabbi Trust - Equity Securities-Mutual Funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	0	[3]
Cash Collateral Netting [Member] | Power [Member] | Rabbi Trust - Debt Securities-Govt Obligations [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	0	[3]
Cash Collateral Netting [Member] | Power [Member] | Rabbi Trust - Debt Securities-Other [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	0	[3]
Cash Collateral Netting [Member] | Power [Member] | Rabbi Trust - Other Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	0	[3]
Cash Collateral Netting [Member] | PSE And G [Member] | Energy-Related Contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total Mark-to-Market Derivative Assets	0	[1]	0	[1]
Total Mark-to-Market Derivative (Liabilities)	0	[1]	0	[1]
Cash Collateral Netting [Member] | PSE And G [Member] | Rabbi Trusts - Mutual Funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total Mark-to-Market Derivative Assets			0	[3]
Cash Collateral Netting [Member] | PSE And G [Member] | Rabbi Trust - Equity Securities-Mutual Funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	0	[3]
Cash Collateral Netting [Member] | PSE And G [Member] | Rabbi Trust - Debt Securities-Govt Obligations [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	0	[3]
Cash Collateral Netting [Member] | PSE And G [Member] | Rabbi Trust - Debt Securities-Other [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	0	[3]
Cash Collateral Netting [Member] | PSE And G [Member] | Rabbi Trust - Other Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	0	[3]
Quoted Market Prices of Identical Assets (Level 1) [Member] | PSEG [Member] | Energy-Related Contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total Mark-to-Market Derivative Assets	0	[1]	0	[1]
Total Mark-to-Market Derivative (Liabilities)	0	[1]	0	[1]
Quoted Market Prices of Identical Assets (Level 1) [Member] | PSEG [Member] | Interest Rate Swap [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total Mark-to-Market Derivative Assets	0	[2]	0	[2]
Total Mark-to-Market Derivative (Liabilities)			0	[2]
Quoted Market Prices of Identical Assets (Level 1) [Member] | PSEG [Member] | Equity Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	728	[3]	685	[3]
Quoted Market Prices of Identical Assets (Level 1) [Member] | PSEG [Member] | Government Obligations [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	0	[3]	0	[3]
Quoted Market Prices of Identical Assets (Level 1) [Member] | PSEG [Member] | Other Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	0	[3]	0	[3]
Quoted Market Prices of Identical Assets (Level 1) [Member] | PSEG [Member] | Other Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	0	[3]	0	[3]
Quoted Market Prices of Identical Assets (Level 1) [Member] | PSEG [Member] | Rabbi Trusts - Mutual Funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments			19	[3]
Quoted Market Prices of Identical Assets (Level 1) [Member] | PSEG [Member] | Non-Recourse Debt [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total Mark-to-Market Derivative (Liabilities)			0	[4]
Quoted Market Prices of Identical Assets (Level 1) [Member] | PSEG [Member] | Rabbi Trust - Equity Securities-Mutual Funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	16	[3]
Quoted Market Prices of Identical Assets (Level 1) [Member] | PSEG [Member] | Rabbi Trust - Debt Securities-Govt Obligations [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	0	[3]
Quoted Market Prices of Identical Assets (Level 1) [Member] | PSEG [Member] | Rabbi Trust - Debt Securities-Other [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	0	[3]
Quoted Market Prices of Identical Assets (Level 1) [Member] | PSEG [Member] | Rabbi Trust - Other Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	0	[3]
Quoted Market Prices of Identical Assets (Level 1) [Member] | Power [Member] | Energy-Related Contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total Mark-to-Market Derivative Assets	0	[1]	0	[1]
Total Mark-to-Market Derivative (Liabilities)	0	[1]	0	[1]
Quoted Market Prices of Identical Assets (Level 1) [Member] | Power [Member] | Equity Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	728	[3]	685	[3]
Quoted Market Prices of Identical Assets (Level 1) [Member] | Power [Member] | Government Obligations [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	0	[3]	0	[3]
Quoted Market Prices of Identical Assets (Level 1) [Member] | Power [Member] | Other Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	0	[3]	0	[3]
Quoted Market Prices of Identical Assets (Level 1) [Member] | Power [Member] | Other Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	0	[3]	0	[3]
Quoted Market Prices of Identical Assets (Level 1) [Member] | Power [Member] | Rabbi Trusts - Mutual Funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments			4	[3]
Quoted Market Prices of Identical Assets (Level 1) [Member] | Power [Member] | Rabbi Trust - Equity Securities-Mutual Funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	3	[3]
Quoted Market Prices of Identical Assets (Level 1) [Member] | Power [Member] | Rabbi Trust - Debt Securities-Govt Obligations [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	0	[3]
Quoted Market Prices of Identical Assets (Level 1) [Member] | Power [Member] | Rabbi Trust - Debt Securities-Other [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	0	[3]
Quoted Market Prices of Identical Assets (Level 1) [Member] | Power [Member] | Rabbi Trust - Other Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	0	[3]
Quoted Market Prices of Identical Assets (Level 1) [Member] | PSE And G [Member] | Energy-Related Contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total Mark-to-Market Derivative Assets	0	[1]	0	[1]
Total Mark-to-Market Derivative (Liabilities)	0	[1]	0	[1]
Quoted Market Prices of Identical Assets (Level 1) [Member] | PSE And G [Member] | Rabbi Trusts - Mutual Funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total Mark-to-Market Derivative Assets			6	[3]
Quoted Market Prices of Identical Assets (Level 1) [Member] | PSE And G [Member] | Rabbi Trust - Equity Securities-Mutual Funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	5	[3]
Quoted Market Prices of Identical Assets (Level 1) [Member] | PSE And G [Member] | Rabbi Trust - Debt Securities-Govt Obligations [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	0	[3]
Quoted Market Prices of Identical Assets (Level 1) [Member] | PSE And G [Member] | Rabbi Trust - Debt Securities-Other [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	0	[3]
Quoted Market Prices of Identical Assets (Level 1) [Member] | PSE And G [Member] | Rabbi Trust - Other Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	0	[3]
Significant Other Observable Inputs (Level 2) [Member] | PSEG [Member] | Energy-Related Contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total Mark-to-Market Derivative Assets	247	[1]	257	[1]
Total Mark-to-Market Derivative (Liabilities)	(106)	[1]	(153)	[1]
Significant Other Observable Inputs (Level 2) [Member] | PSEG [Member] | Interest Rate Swap [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total Mark-to-Market Derivative Assets	66	[2]	64	[2]
Total Mark-to-Market Derivative (Liabilities)			(2)	[2]
Significant Other Observable Inputs (Level 2) [Member] | PSEG [Member] | Equity Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	0	[3]	0	[3]
Significant Other Observable Inputs (Level 2) [Member] | PSEG [Member] | Government Obligations [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	306	[3]	359	[3]
Significant Other Observable Inputs (Level 2) [Member] | PSEG [Member] | Other Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	320	[3]	281	[3]
Significant Other Observable Inputs (Level 2) [Member] | PSEG [Member] | Other Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	62	[3]	24	[3]
Significant Other Observable Inputs (Level 2) [Member] | PSEG [Member] | Rabbi Trusts - Mutual Funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments			153	[3]
Significant Other Observable Inputs (Level 2) [Member] | PSEG [Member] | Non-Recourse Debt [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total Mark-to-Market Derivative (Liabilities)			0	[4]
Significant Other Observable Inputs (Level 2) [Member] | PSEG [Member] | Rabbi Trust - Equity Securities-Mutual Funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	0	[3]
Significant Other Observable Inputs (Level 2) [Member] | PSEG [Member] | Rabbi Trust - Debt Securities-Govt Obligations [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	116	[3]
Significant Other Observable Inputs (Level 2) [Member] | PSEG [Member] | Rabbi Trust - Debt Securities-Other [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	44	[3]
Significant Other Observable Inputs (Level 2) [Member] | PSEG [Member] | Rabbi Trust - Other Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	3	[3]
Significant Other Observable Inputs (Level 2) [Member] | Power [Member] | Energy-Related Contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total Mark-to-Market Derivative Assets	247	[1]	257	[1]
Total Mark-to-Market Derivative (Liabilities)	(106)	[1]	(153)	[1]
Significant Other Observable Inputs (Level 2) [Member] | Power [Member] | Equity Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	0	[3]	0	[3]
Significant Other Observable Inputs (Level 2) [Member] | Power [Member] | Government Obligations [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	306	[3]	359	[3]
Significant Other Observable Inputs (Level 2) [Member] | Power [Member] | Other Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	320	[3]	281	[3]
Significant Other Observable Inputs (Level 2) [Member] | Power [Member] | Other Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	62	[3]	24	[3]
Significant Other Observable Inputs (Level 2) [Member] | Power [Member] | Rabbi Trusts - Mutual Funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments			29	[3]
Significant Other Observable Inputs (Level 2) [Member] | Power [Member] | Rabbi Trust - Equity Securities-Mutual Funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	0	[3]
Significant Other Observable Inputs (Level 2) [Member] | Power [Member] | Rabbi Trust - Debt Securities-Govt Obligations [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	23	[3]
Significant Other Observable Inputs (Level 2) [Member] | Power [Member] | Rabbi Trust - Debt Securities-Other [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	8	[3]
Significant Other Observable Inputs (Level 2) [Member] | Power [Member] | Rabbi Trust - Other Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	1	[3]
Significant Other Observable Inputs (Level 2) [Member] | PSE And G [Member] | Energy-Related Contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total Mark-to-Market Derivative Assets	0	[1]	0	[1]
Total Mark-to-Market Derivative (Liabilities)	0	[1]	0	[1]
Significant Other Observable Inputs (Level 2) [Member] | PSE And G [Member] | Rabbi Trusts - Mutual Funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total Mark-to-Market Derivative Assets			51	[3]
Significant Other Observable Inputs (Level 2) [Member] | PSE And G [Member] | Rabbi Trust - Equity Securities-Mutual Funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	0	[3]
Significant Other Observable Inputs (Level 2) [Member] | PSE And G [Member] | Rabbi Trust - Debt Securities-Govt Obligations [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	38	[3]
Significant Other Observable Inputs (Level 2) [Member] | PSE And G [Member] | Rabbi Trust - Debt Securities-Other [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	15	[3]
Significant Other Observable Inputs (Level 2) [Member] | PSE And G [Member] | Rabbi Trust - Other Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	1	[3]
Significant Unobservable Inputs (Level 3) [Member] | PSEG [Member] | Energy-Related Contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total Mark-to-Market Derivative Assets	68	[1]	41	[1]
Total Mark-to-Market Derivative (Liabilities)	(104)	[1]	(20)	[1]
Significant Unobservable Inputs (Level 3) [Member] | PSEG [Member] | Interest Rate Swap [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total Mark-to-Market Derivative Assets	0	[2]	0	[2]
Total Mark-to-Market Derivative (Liabilities)			0	[2]
Significant Unobservable Inputs (Level 3) [Member] | PSEG [Member] | Equity Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	0	[3]	0	[3]
Significant Unobservable Inputs (Level 3) [Member] | PSEG [Member] | Government Obligations [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	0	[3]	0	[3]
Significant Unobservable Inputs (Level 3) [Member] | PSEG [Member] | Other Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	0	[3]	0	[3]
Significant Unobservable Inputs (Level 3) [Member] | PSEG [Member] | Other Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	0	[3]	0	[3]
Significant Unobservable Inputs (Level 3) [Member] | PSEG [Member] | Rabbi Trusts - Mutual Funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments			0	[3]
Significant Unobservable Inputs (Level 3) [Member] | PSEG [Member] | Non-Recourse Debt [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total Mark-to-Market Derivative (Liabilities)			(50)	[4]
Significant Unobservable Inputs (Level 3) [Member] | PSEG [Member] | Rabbi Trust - Equity Securities-Mutual Funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	0	[3]
Significant Unobservable Inputs (Level 3) [Member] | PSEG [Member] | Rabbi Trust - Debt Securities-Govt Obligations [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	0	[3]
Significant Unobservable Inputs (Level 3) [Member] | PSEG [Member] | Rabbi Trust - Debt Securities-Other [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	0	[3]
Significant Unobservable Inputs (Level 3) [Member] | PSEG [Member] | Rabbi Trust - Other Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	0	[3]
Significant Unobservable Inputs (Level 3) [Member] | Power [Member] | Energy-Related Contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total Mark-to-Market Derivative Assets	22	[1]	37	[1]
Total Mark-to-Market Derivative (Liabilities)	0	[1]	(13)	[1]
Significant Unobservable Inputs (Level 3) [Member] | Power [Member] | Equity Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	0	[3]	0	[3]
Significant Unobservable Inputs (Level 3) [Member] | Power [Member] | Government Obligations [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	0	[3]	0	[3]
Significant Unobservable Inputs (Level 3) [Member] | Power [Member] | Other Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	0	[3]	0	[3]
Significant Unobservable Inputs (Level 3) [Member] | Power [Member] | Other Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	0	[3]	0	[3]
Significant Unobservable Inputs (Level 3) [Member] | Power [Member] | Rabbi Trusts - Mutual Funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments			0	[3]
Significant Unobservable Inputs (Level 3) [Member] | Power [Member] | Rabbi Trust - Equity Securities-Mutual Funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	0	[3]
Significant Unobservable Inputs (Level 3) [Member] | Power [Member] | Rabbi Trust - Debt Securities-Govt Obligations [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	0	[3]
Significant Unobservable Inputs (Level 3) [Member] | Power [Member] | Rabbi Trust - Debt Securities-Other [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	0	[3]
Significant Unobservable Inputs (Level 3) [Member] | Power [Member] | Rabbi Trust - Other Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	0	[3]
Significant Unobservable Inputs (Level 3) [Member] | PSE And G [Member] | Energy-Related Contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total Mark-to-Market Derivative Assets	46	[1]	4	[1]
Total Mark-to-Market Derivative (Liabilities)	(104)	[1]	(7)	[1]
Significant Unobservable Inputs (Level 3) [Member] | PSE And G [Member] | Rabbi Trusts - Mutual Funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total Mark-to-Market Derivative Assets			0	[3]
Significant Unobservable Inputs (Level 3) [Member] | PSE And G [Member] | Rabbi Trust - Equity Securities-Mutual Funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	0	[3]
Significant Unobservable Inputs (Level 3) [Member] | PSE And G [Member] | Rabbi Trust - Debt Securities-Govt Obligations [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	0	[3]
Significant Unobservable Inputs (Level 3) [Member] | PSE And G [Member] | Rabbi Trust - Debt Securities-Other [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	0	[3]
Significant Unobservable Inputs (Level 3) [Member] | PSE And G [Member] | Rabbi Trust - Other Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measured on Recurring Basis, Investments	$ 0	[3]

[1] Level 2-Fair values for energy-related contracts are obtained primarily using a market-based approach. Most derivative contracts (forward purchase or sale contracts and swaps) are valued using the average of the bid/ask midpoints from multiple broker or dealer quotes or auction prices. Prices used in the valuation process are also corroborated independently by management to determine that values are based on actual transaction data or, in the absence of transactions, bid and offers for the day. Examples may include certain exchange and non-exchange traded capacity and electricity contracts and natural gas physical or swap contracts based on market prices, basis adjustments and other premiums where adjustments and premiums are not considered significant to the overall inputs. Level 3-For energy-related contracts, which include more complex agreements where limited observable inputs or pricing information are available, modeling techniques are employed using assumptions reflective of contractual terms, current market rates, forward price curves, discount rates and risk factors, as applicable. Fair values of other energy contracts may be based on broker quotes that we cannot corroborate with actual market transaction data.

[2] Interest rate swaps are valued using quoted prices on commonly quoted intervals, which are interpolated for periods different than the quoted intervals, as inputs to a market valuation model. Market inputs can generally be verified and model selection does not involve significant management judgment.

[3] The fair value measurements table excludes cash of $1 million which is part of the NDT Fund as of June 30, 2012. The NDT Fund maintains investments in various equity and fixed income securities classified as "available for sale." The Rabbi Trust maintains investments in an S&P 500 index fund and various fixed income securities classified as "available for sale." These securities are generally valued with prices that are either exchange provided (equity securities) or market transactions for comparable securities and/or broker quotes (fixed income securities). Level 1-Investments in marketable equity securities within the NDT Fund are primarily investments in common stocks across a broad range of industries and sectors. Most equity securities are priced utilizing the principal market close price or, in some cases, midpoint, bid or ask price (primarily Level 1). The Rabbi Trust equity index fund is valued based on quoted prices in an active market (Level 1). Level 2-NDT and Rabbi Trust fixed income securities are limited to investment grade corporate bonds and United States Treasury obligations or Federal Agency mortgage-backed securities with a wide range of maturities. Since many fixed income securities do not trade on a daily basis, they are priced using an evaluated pricing methodology that varies by asset class and reflects observable market information such as the most recent exchange price or quoted bid for similar securities. Market-based standard inputs typically include benchmark yields, reported trades, broker/dealer quotes, and issuer spreads (primarily Level 2). Short-term investments and certain commingled temporary investments are valued using observable market prices or market parameters such as time-to-maturity, coupon rate, quality rating and current yield (primarily Level 2).

[4] For Non-Recourse Debt, see Fair Value Option below.