Financial Information By Business Segments (Financial Information By Business Segments) (Detail) - USD ($) $ in Millions		3 Months Ended		6 Months Ended
		Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Segment Reporting Information [Line Items]
Operating Revenues		$ 2,050	$ 2,316	$ 4,831	$ 5,296
Net Income (Loss)		451	153	899	853
Property, Plant and Equipment, Additions		694	809	1,414	1,604
Total Assets		48,780		48,780		$ 47,730
Investments in Equity Method Subsidiaries		68		68		67
Public Service Electric and Gas Company [Member]
Segment Reporting Information [Line Items]
Operating Revenues		1,456	1,382	3,339	3,414
PSEG Power [Member]
Segment Reporting Information [Line Items]
Operating Revenues		683	1,083	1,903	2,499
Other [Member]
Segment Reporting Information [Line Items]
Operating Revenues		148	87	304	228
Operating Segments [Member] | Public Service Electric and Gas Company [Member]
Segment Reporting Information [Line Items]
Operating Revenues		1,456	1,382	3,339	3,414
Net Income (Loss)		283	227	723	630
Property, Plant and Equipment, Additions		570	633	1,190	1,258
Total Assets		34,445		34,445		33,266
Investments in Equity Method Subsidiaries		0		0		0
Operating Segments [Member] | PSEG Power [Member]
Segment Reporting Information [Line Items]
Operating Revenues		683	1,083	1,903	2,499
Net Income (Loss)		170	(40)	183	256
Property, Plant and Equipment, Additions		121	172	218	339
Total Assets		12,508		12,508		12,805
Investments in Equity Method Subsidiaries		67		67		66
Operating Segments [Member] | Other [Member]
Segment Reporting Information [Line Items]
Operating Revenues	[1]	148	87	304	228
Net Income (Loss)	[1]	(2)	(34)	(7)	(33)
Property, Plant and Equipment, Additions	[1]	3	4	6	7
Total Assets	[1]	2,618		2,618		2,715
Investments in Equity Method Subsidiaries	[1]	1		1		1
Eliminations [Member]
Segment Reporting Information [Line Items]
Operating Revenues	[2]	(237)	(236)	(715)	(845)
Net Income (Loss)	[2]	0	0	0
Property, Plant and Equipment, Additions	[2]	0	0	0	0
Total Assets	[2]	(791)		(791)		(1,056)
Investments in Equity Method Subsidiaries	[2]	0		0		0
PSEG Power [Member]
Segment Reporting Information [Line Items]
Operating Revenues		683	1,083	1,903	2,499
Net Income (Loss)		170	$ (40)	183	$ 256
Total Assets		$ 12,508		$ 12,508		$ 12,805

[1] Includes amounts applicable to Energy Holdings and PSEG LI, which are below the quantitative threshold for separate disclosure as reportable segments. Other also includes amounts applicable to PSEG (parent company) and Services.

[2] Intercompany eliminations primarily relate to intercompany transactions between PSE&G and PSEG Power. For a further discussion of the intercompany transactions between PSE&G and PSEG Power, see Note 20. Related-Party Transactions.