Debt and Credit Facilities Debt and Credit Facilities (Short-Term Liquidity) (Details) - USD ($) $ in Millions		9 Months Ended
		Sep. 30, 2018	Dec. 31, 2017
Commercial Paper		$ 419	$ 542
Commitments of Single Institution as Percentage of Total Commitments		9.00%
Line of Credit Facility, Remaining Borrowing Capacity		$ 3,638
Line of Credit Facility, Maximum Borrowing Capacity		4,300
Line of Credit Facility, Fair Value of Amount Outstanding		662
PSE And G [Member]
Commercial Paper		40	$ 0
Line of Credit Facility, Remaining Borrowing Capacity		544
Line of Credit Facility, Maximum Borrowing Capacity		600
Line of Credit Facility, Fair Value of Amount Outstanding	[1]	56
Power [Member]
Line of Credit Facility, Remaining Borrowing Capacity		1,987
Line of Credit Facility, Maximum Borrowing Capacity		2,200
Line of Credit Facility, Fair Value of Amount Outstanding		213
Five Year Credit Facility Maturing March 2022 [Member] | PSE And G [Member]
Line of Credit Facility, Remaining Borrowing Capacity		$ 544
Debt Instrument, Maturity Date, Description		Mar 2022
Line of Credit Facility, Maximum Borrowing Capacity		$ 600
Line of Credit Facility, Fair Value of Amount Outstanding		56
Five Year Credit Facility Maturing March 2022 [Member] | Power [Member]
Line of Credit Facility, Remaining Borrowing Capacity		$ 1,849
Debt Instrument, Maturity Date, Description		Mar 2022
Line of Credit Facility, Maximum Borrowing Capacity		$ 1,900
Line of Credit Facility, Fair Value of Amount Outstanding		51
Three Year Credit Facilities Maturing March 2020 [Member] | Power [Member]
Line of Credit Facility, Remaining Borrowing Capacity		$ 38
Debt Instrument, Maturity Date, Description		Mar 2020
Line of Credit Facility, Maximum Borrowing Capacity		$ 100
Line of Credit Facility, Fair Value of Amount Outstanding		62
Three Year Credit Facilities Maturing September 2021 [Member] | Power [Member]
Line of Credit Facility, Remaining Borrowing Capacity		$ 100
Debt Instrument, Maturity Date, Description		Sept 2021
Line of Credit Facility, Maximum Borrowing Capacity		$ 200
Line of Credit Facility, Fair Value of Amount Outstanding		100
Five Year Credit Facility Maturing March 2022 [Member] | PSE And G [Member]
Commercial Paper		$ 40
Short-term Debt, Weighted Average Interest Rate, at Point in Time		2.35%
PSEG [Member]
Line of Credit Facility, Remaining Borrowing Capacity		$ 1,107
Line of Credit Facility, Maximum Borrowing Capacity		1,500
Line of Credit Facility, Fair Value of Amount Outstanding	[1]	393
PSEG [Member] | Five Year Credit Facility Maturing March 2022 [Member]
Line of Credit Facility, Remaining Borrowing Capacity		$ 1,107
Debt Instrument, Maturity Date, Description		Mar 2022
Line of Credit Facility, Maximum Borrowing Capacity		$ 1,500
Line of Credit Facility, Fair Value of Amount Outstanding		393
PSEG [Member] | Five Year Credit Facility Maturing March 2022 [Member]
Commercial Paper		$ 379
Short-term Debt, Weighted Average Interest Rate, at Point in Time		2.54%

[1] The primary use of PSEG’s and PSE&G’s credit facilities is to support their respective Commercial Paper Programs, under which as of September 30, 2018, PSEG had $379 million outstanding at a weighted average interest rate of 2.54%. PSE&G had $40 million outstanding at a weighted average interest rate of 2.35% under its Commercial Paper Program as of September 30, 2018.