Commitments And Contingent Liabilities (Basic Generation Service (BGS) And Basic Gas Supply Service (BGSS)) (Detail) cf in Billions	9 Months Ended
	Sep. 30, 2017 cf $ / mwd $ / mwh MW
Long-term Purchase Commitment [Line Items]
Number of cubic feet in gas hedging permitted to be recovered by BPU | cf	115
Percentage of residential gas supply permitted to be recovered in gas hedging by BPU	80.00%
Number of cubic feet to be hedged | cf	70
Percentage of annual residential gas supply requirements to be hedged	50.00%
PSE And G [Member] | Auction Year 2014 [Member]
Long-term Purchase Commitment [Line Items]
36-Month Terms Ending	May 31, 2017
Load (MW) | MW	2,800
Dollars Per Megawatt Hour | $ / mwh	97.39
PSE And G [Member] | Auction Year 2015 [Member]
Long-term Purchase Commitment [Line Items]
36-Month Terms Ending	May 31, 2018
Load (MW) | MW	2,900
Dollars Per Megawatt Hour | $ / mwh	99.54
PSE And G [Member] | Auction Year 2016 [Member]
Long-term Purchase Commitment [Line Items]
Dollars Per Megawatt-Day | $ / mwd	335.33
36-Month Terms Ending	May 31, 2019
Load (MW) | MW	2,800
Dollars Per Megawatt Hour | $ / mwh	96.38
PSE And G [Member] | Auction Year 2017 [Member]
Long-term Purchase Commitment [Line Items]
Dollars Per Megawatt-Day | $ / mwd	276.83
36-Month Terms Ending	May 31, 2020
Load (MW) | MW	2,800
Dollars Per Megawatt Hour | $ / mwh	90.78