Commitments And Contingent Liabilities (Guaranteed Obligations) (Detail) (Power [Member], USD $) In Millions, unless otherwise specified	Sep. 30, 2014	Dec. 31, 2013
Power [Member]
Face Value of Outstanding Guarantees	$ 1,719	$ 1,639
Exposure under Current Guarantees	222	246
Letters of Credit Margin Posted	138	132
Letters of Credit Margin Received	17	25
Counterparty Cash Margin Deposited	0	0
Counterparty Cash Margin Received	(25)	0
Net Broker Balance Deposited (Received)	278	80
Additional Collateral that could be Required	851	691
Liquidity Available under PSEG's and Power's Credit Facilities to Post Collateral	3,516	3,522
Other Letters of Credit	$ 45	$ 45