Financial Information By Business Segments (Financial Information By Business Segments) (Detail) - USD ($)
$ in Millions
 3 Months Ended
Mar. 31, 2018
Mar. 31, 2017
Dec. 31, 2017
Segment Reporting Information [Line Items]      
Operating Revenues $ 2,818 $ 2,591  
Net Income (Loss) 558 114  
Property, Plant and Equipment, Additions 1,053 1,062  
Total Assets 42,790   $ 42,716
Investments in Equity Method Subsidiaries 86   87
PSE And G [Member]      
Segment Reporting Information [Line Items]      
Operating Revenues 1,845 1,826  
Power [Member]      
Segment Reporting Information [Line Items]      
Operating Revenues 1,403 1,269  
Other [Member]      
Segment Reporting Information [Line Items]      
Operating Revenues 147 83  
Operating Segments [Member] | PSE And G [Member]      
Segment Reporting Information [Line Items]      
Operating Revenues 1,845 1,826  
Net Income (Loss) 319 299  
Property, Plant and Equipment, Additions 750 748  
Total Assets 28,774   28,554
Investments in Equity Method Subsidiaries 0   0
Operating Segments [Member] | Power [Member]      
Segment Reporting Information [Line Items]      
Operating Revenues 1,403 1,269  
Net Income (Loss) 234 (170)  
Property, Plant and Equipment, Additions 299 307  
Total Assets 12,263   12,418
Investments in Equity Method Subsidiaries 86   87
Operating Segments [Member] | Other [Member]      
Segment Reporting Information [Line Items]      
Operating Revenues [1] 147 83  
Net Income (Loss) [1] 5 (15)  
Property, Plant and Equipment, Additions [1] 4 7  
Total Assets [1] 2,481   2,666
Investments in Equity Method Subsidiaries [1] 0   0
Eliminations [Member]      
Segment Reporting Information [Line Items]      
Operating Revenues [2] (577) (587)  
Net Income (Loss) [2] 0 0  
Property, Plant and Equipment, Additions [2] 0 $ 0  
Total Assets [2] (728)   (922)
Investments in Equity Method Subsidiaries [2] $ 0   $ 0
[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 corporation) and Services.
[2] Intercompany eliminations primarily relate to intercompany transactions between PSE&G and Power. For a further discussion of the intercompany transactions between PSE&G and Power, see Note 19. Related-Party Transactions.