Financial Information By Business Segments (Financial Information By Business Segments) (Detail) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Segment Reporting Information [Line Items]
Operating Revenues		$ 2,781	$ 2,980
Net Income		448	700
Property, Plant and Equipment, Additions		720	795
Total Assets		48,365		$ 47,730
Investments in Equity Method Subsidiaries		69		67
Public Service Electric and Gas Company [Member]
Segment Reporting Information [Line Items]
Operating Revenues		1,883	2,032
PSEG Power [Member]
Segment Reporting Information [Line Items]
Operating Revenues		1,220	1,416
Other [Member]
Segment Reporting Information [Line Items]
Operating Revenues		156	141
Operating Segments [Member] | Public Service Electric and Gas Company [Member]
Segment Reporting Information [Line Items]
Operating Revenues		1,883	2,032
Net Income		440	403
Property, Plant and Equipment, Additions		620	625
Total Assets		33,627		33,266
Investments in Equity Method Subsidiaries		0		0
Operating Segments [Member] | PSEG Power [Member]
Segment Reporting Information [Line Items]
Operating Revenues		1,220	1,416
Net Income		13	296
Property, Plant and Equipment, Additions		97	167
Total Assets		12,847		12,805
Investments in Equity Method Subsidiaries		68		66
Operating Segments [Member] | Other [Member]
Segment Reporting Information [Line Items]
Operating Revenues	[1]	156	141
Net Income	[1]	(5)	1
Property, Plant and Equipment, Additions	[1]	3	3
Total Assets	[1]	3,296		2,715
Investments in Equity Method Subsidiaries	[1]	1		1
Eliminations [Member]
Segment Reporting Information [Line Items]
Operating Revenues	[2]	(478)	(609)
Net Income	[2]	0
Property, Plant and Equipment, Additions	[2]	0	0
Total Assets	[2]	(1,405)		(1,056)
Investments in Equity Method Subsidiaries	[2]	0		0
PSEG Power [Member]
Segment Reporting Information [Line Items]
Operating Revenues		1,220	1,416
Net Income		13	$ 296
Total Assets		$ 12,847		$ 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.