Commitments And Contingent Liabilities (Guaranteed Obligations) (Detail) - PSEG Power [Member] - USD ($) $ in Millions	Sep. 30, 2019	Dec. 31, 2018
Loss Contingencies [Line Items]
Face Value of Outstanding Guarantees	$ 1,827	$ 1,772
Exposure under Current Guarantees	134	198
Letters of Credit Margin Posted	137	115
Letters of Credit Margin Received	34	26
Counterparty Cash Margin Deposited	0	0
Counterparty Cash Margin Received	(3)	(10)
Net Broker Balance Deposited (Received)	95	403
Other Letters of Credit	$ 53	$ 52