Debt and Credit Facilities Debt and Credit Facilities (Short-Term Liquidity) (Details) - USD ($) $ in Millions		6 Months Ended
		Jun. 30, 2018	Dec. 31, 2017
Commercial Paper		$ 270	$ 542
Commitments of Single Institution as Percentage of Total Commitments		8.00%
Line of Credit Facility, Remaining Borrowing Capacity		$ 3,699
Line of Credit Facility, Maximum Borrowing Capacity		4,200
Line of Credit Facility, Fair Value of Amount Outstanding		501
PSE And G [Member]
Commercial Paper		195	$ 0
Line of Credit Facility, Remaining Borrowing Capacity		389
Line of Credit Facility, Maximum Borrowing Capacity		600
Line of Credit Facility, Fair Value of Amount Outstanding	[1]	211
Power [Member]
Line of Credit Facility, Remaining Borrowing Capacity		1,898
Line of Credit Facility, Maximum Borrowing Capacity		2,100
Line of Credit Facility, Fair Value of Amount Outstanding		202
Five Year Credit Facility Maturing March 2022 [Member] | PSE And G [Member]
Line of Credit Facility, Remaining Borrowing Capacity		$ 389
Debt Instrument, Maturity Date, Description		Mar 2022
Line of Credit Facility, Maximum Borrowing Capacity		$ 600
Line of Credit Facility, Fair Value of Amount Outstanding		211
Five Year Credit Facility Maturing March 2022 [Member] | Power [Member]
Line of Credit Facility, Remaining Borrowing Capacity		$ 1,860
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		40
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		$ 200
Line of Credit Facility, Fair Value of Amount Outstanding		162
Five Year Credit Facility Maturing March 2022 [Member] | PSE And G [Member]
Commercial Paper		$ 195
Short-term Debt, Weighted Average Interest Rate, at Point in Time		2.29%
PSEG [Member]
Line of Credit Facility, Remaining Borrowing Capacity		$ 1,412
Line of Credit Facility, Maximum Borrowing Capacity		1,500
Line of Credit Facility, Fair Value of Amount Outstanding	[1]	88
PSEG [Member] | Five Year Credit Facility Maturing March 2022 [Member]
Line of Credit Facility, Remaining Borrowing Capacity		$ 1,412
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		88
PSEG [Member] | Five Year Credit Facility Maturing March 2022 [Member]
Commercial Paper		$ 75
Short-term Debt, Weighted Average Interest Rate, at Point in Time		2.32%

[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 June 30, 2018, PSEG had $75 million outstanding at a weighted average interest rate of 2.32%. PSE&G had $195 million outstanding at a weighted average interest rate of 2.29% under its Commercial Paper Program as of June 30, 2018.