Commitments And Contingent Liabilities (Guaranteed Obligations) (Detail) - PSEG Power [Member] - USD ($) $ in Millions	Jun. 30, 2020	Dec. 31, 2019
Loss Contingencies [Line Items]
Face Value of Outstanding Guarantees	$ 1,828	$ 1,854
Exposure under Current Guarantees	113	171
Letters of Credit Margin Posted	95	121
Letters of Credit Margin Received	75	29
Counterparty Cash Collateral Deposited	0	0
Counterparty Cash Collateral Received	(4)	(4)
Net Broker Balance Deposited (Received)	16	48
Other Letters of Credit	$ 83	$ 82