Financial Risk Management Activities (Schedule Of Derivative Instruments Fair Value In Balance Sheets) (Detail) - USD ($) $ in Millions		Sep. 30, 2021	Jun. 30, 2021	Dec. 31, 2020
Derivatives, Fair Value [Line Items]
Derivative Contracts, Current Assets		$ 137		$ 60
Derivative Contracts, Noncurrent Assets		16		9
Total Mark-to-Market Derivative Assets		153		69
Derivative Contracts, Current Liabilities		(56)		(21)
Derivative Contracts, Noncurrent Liabilities		(17)		(4)
Total Mark-to-Market Derivative (Liabilities)		(73)		(25)
Net Mark-to-Market Derivative Assets (Liabilities)		80		44
PSEG Power [Member]
Derivatives, Fair Value [Line Items]
Collateral Already Posted, Aggregate Fair Value		999	$ 343	54
Derivative Contracts, Current Assets	[1]	137		60
Derivative Contracts, Noncurrent Assets	[1]	16		9
Total Mark-to-Market Derivative Assets	[1]	153		69
Derivative Contracts, Current Liabilities	[1]	(56)		(21)
Derivative Contracts, Noncurrent Liabilities	[1]	(17)		(4)
Total Mark-to-Market Derivative (Liabilities)	[1]	(73)		(25)
Net Mark-to-Market Derivative Assets (Liabilities)	[1]	80		44
Derivative, Fair Value, Amount Offset Against Collateral, Net	[1],[2]	917		8
Other Noncurrent Liabilities [Member] | PSEG Power [Member]
Derivatives, Fair Value [Line Items]
Derivative, Fair Value, Amount Offset Against Collateral, Net		241		21
Other Current Assets [Member] | PSEG Power [Member]
Derivatives, Fair Value [Line Items]
Derivative, Fair Value, Amount Offset Against Collateral, Net				(13)
Other Current Liabilities [Member] | PSEG Power [Member]
Derivatives, Fair Value [Line Items]
Derivative, Fair Value, Amount Offset Against Collateral, Net		676
Energy-Related Contracts [Member] | Not Designated as Hedging Instrument [Member] | PSEG Power [Member]
Derivatives, Fair Value [Line Items]
Derivative Contracts, Current Assets	[1]	2,006		464
Derivative Contracts, Noncurrent Assets	[1]	449		93
Total Mark-to-Market Derivative Assets	[1]	2,455		557
Derivative Contracts, Current Liabilities	[1]	(2,601)		(412)
Derivative Contracts, Noncurrent Liabilities	[1]	(691)		(109)
Total Mark-to-Market Derivative (Liabilities)	[1]	(3,292)		(521)
Net Mark-to-Market Derivative Assets (Liabilities)	[1]	(837)		36
Energy-Related Contracts [Member] | Other Noncurrent Liabilities [Member] | PSEG Power [Member]
Derivatives, Fair Value [Line Items]
Derivative, Fair Value, Amount Offset Against Collateral, Net	[1],[2]	674		105
Energy-Related Contracts [Member] | Other Current Assets [Member] | PSEG Power [Member]
Derivatives, Fair Value [Line Items]
Derivative, Fair Value, Amount Offset Against Collateral, Net	[1],[2]	(1,869)		(404)
Energy-Related Contracts [Member] | Other Noncurrent Assets [Member] | PSEG Power [Member]
Derivatives, Fair Value [Line Items]
Derivative, Fair Value, Amount Offset Against Collateral, Net	[1],[2]	(433)		(84)
Energy-Related Contracts [Member] | Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative, Fair Value, Amount Offset Against Collateral, Net	[3]	(2,302)		(488)
Energy-Related Contracts [Member] | Assets [Member] | PSEG Power [Member]
Derivatives, Fair Value [Line Items]
Derivative, Fair Value, Amount Offset Against Collateral, Net	[1],[2],[3]	(2,302)		(488)
Energy-Related Contracts [Member] | Other Current Liabilities [Member] | PSEG Power [Member]
Derivatives, Fair Value [Line Items]
Derivative, Fair Value, Amount Offset Against Collateral, Net	[1],[2]	2,545		391
Energy-Related Contracts [Member] | Other Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative, Fair Value, Amount Offset Against Collateral, Net	[3]	3,219		496
Energy-Related Contracts [Member] | Other Liabilities [Member] | PSEG Power [Member]
Derivatives, Fair Value [Line Items]
Derivative, Fair Value, Amount Offset Against Collateral, Net	[1],[2],[3]	$ 3,219		$ 496

[1] Substantially all of PSEG Power’s and PSEG’s derivative instruments are contracts subject to master netting agreements. Contracts not subject to master netting or similar agreements are immaterial and did not have any collateral posted or received as of September 30, 2021 and December 31, 2020.

[2] Represents the netting of fair value balances with the same counterparty (where the right of offset exists) and the application of collateral. All cash collateral (received) posted that has been allocated to derivative positions, where the right of offset exists, has been offset on the Condensed Consolidated Balance Sheets. As of September 30, 2021 and December 31, 2020, PSEG Power had net cash collateral (receipts) payments to counterparties of $999 million and $54 million, respectively. Of these net cash collateral (receipts) payments, $917 million and $8 million as of September 30, 2021 and December 31, 2020, respectively, were netted against the corresponding net derivative contract positions. Of the $917 million as of September 30, 2021, $676 million was netted against current liabilities and $241 million was netted against noncurrent liabilities. Of the $8 million as of December 31, 2020, $(13) million was netted against current assets and $21 million was netted against noncurrent liabilities.

[3] Represents the netting of fair value balances with the same counterparty (where the right of offset exists) and the application of collateral. See Note 13. Financial Risk Management Activities for additional detail.