Debt and Credit Facilities (Long-Term Debt Financing Transactions) (Details) - USD ($) $ in Millions		1 Months Ended	12 Months Ended
		Jan. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Commercial Paper			$ 1,115	$ 1,016
Issuance of Long-Term Debt			1,900	2,750	$ 2,175
Long-term Debt			15,208
PSEG [Member]
Debt Instrument [Line Items]
Long-term Debt			2,450	2,450
PSEG [Member] | Senior Notes Two Point Eight Seven Five Percent due Two Thousand Twenty Four [Member]
Debt Instrument [Line Items]
Issuance of Long-Term Debt			750
Debt Instrument, Face Amount			$ 750
Stated interest rate of debt instrument			2.875%
PSEG [Member] | Term Loan maturing in 2020 [Member]
Debt Instrument [Line Items]
Long-term Debt			$ 700	700
PSEG [Member] | Term Loan maturing in 2019 [Member]
Debt Instrument [Line Items]
Long-term Debt			0	350
Repayments of Long-term Debt			350
PSEG [Member] | Senior Notes One Point Six Zero Percent Due In Two Thousand Nineteen [Member]
Debt Instrument [Line Items]
Long-term Debt			$ 0	400
Stated interest rate of debt instrument			1.60%
Repayments of Long-term Debt			$ 400
Public Service Electric and Gas Company
Debt Instrument [Line Items]
Commercial Paper			362	272
Issuance of Long-Term Debt			1,150	1,350	775
Long-term Debt			9,908	9,258
Public Service Electric and Gas Company | Medium Term Notes Three Point Seven Zero Percent due Two Thousand Twenty Eight [Member]
Debt Instrument [Line Items]
Long-term Debt	[1]		$ 375	375
Stated interest rate of debt instrument			3.70%
Public Service Electric and Gas Company | Medium Term Notes Four Point Zero Five Percent due Two Thousand Forty Eight [Member]
Debt Instrument [Line Items]
Long-term Debt	[1]		$ 325	325
Stated interest rate of debt instrument			4.05%
Public Service Electric and Gas Company | Medium Term Notes Three Point Two Five Percent due Two Thousand Twenty Three [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	[1]		$ 325	325
Stated interest rate of debt instrument			3.25%
Public Service Electric and Gas Company | Medium Term Notes Three Point Six Five Percent due Two Thousand Twenty Eight [Member]
Debt Instrument [Line Items]
Long-term Debt	[1]		$ 325	325
Stated interest rate of debt instrument			3.65%
Public Service Electric and Gas Company | Medium Term Notes Three Point Two Zero Percent due Two Thousand Forty NIne [Member]
Debt Instrument [Line Items]
Issuance of Long-Term Debt			$ 400
Long-term Debt	[1]		$ 400	0
Stated interest rate of debt instrument			3.20%
Public Service Electric and Gas Company | Medium Term Notes Three Point Two Zero Percent due Two Thousand Twenty NIne [Member]
Debt Instrument [Line Items]
Issuance of Long-Term Debt			$ 375
Long-term Debt	[1]		$ 375	0
Stated interest rate of debt instrument			3.20%
Public Service Electric and Gas Company | Medium Term Notes Three Point Eight Five Percent due Two Thousand Forty Nine [Member]
Debt Instrument [Line Items]
Issuance of Long-Term Debt			$ 375
Long-term Debt	[1]		$ 375	0
Stated interest rate of debt instrument			3.85%
Public Service Electric and Gas Company | Medium Term Notes One Point Eight Percent Due In Two Thousand Nineteen [Member] [Domain]
Debt Instrument [Line Items]
Long-term Debt	[1]		$ 0	250
Stated interest rate of debt instrument			1.80%
Repayments of Long-term Debt			$ 250
Public Service Electric and Gas Company | Medium Term Notes Two Point Zero Percent due Two Thousand Nineteen [Member]
Debt Instrument [Line Items]
Stated interest rate of debt instrument			2.00%
Repayments of Long-term Debt			$ 250
Public Service Electric and Gas Company | Medium Term Notes Two Point Four Five Percent due Two Thousand Thirty [Member]
Debt Instrument [Line Items]
Stated interest rate of debt instrument			2.45%
Public Service Electric and Gas Company | Medium Term Notes Three Point One Five Percent due Two Thousand Fifty [Member]
Debt Instrument [Line Items]
Stated interest rate of debt instrument			3.15%
PSEG Power LLC
Debt Instrument [Line Items]
Issuance of Long-Term Debt			$ 0	700	$ 0
Long-term Debt			2,850	2,850
PSEG Power LLC | Senior Notes Three Point Eight Five Percent due Two Thousand Twenty Three [Member]
Debt Instrument [Line Items]
Long-term Debt			$ 700	$ 700
Stated interest rate of debt instrument			3.85%
PSEG Power LLC | Pollution Control Notes Floating Rate Due On Two Thousand Twenty Two [Member]
Debt Instrument [Line Items]
Long-term Debt			$ 44
Subsequent Event [Member] | Public Service Electric and Gas Company | Medium Term Notes Two Point Four Five Percent due Two Thousand Thirty [Member]
Debt Instrument [Line Items]
Issuance of Long-Term Debt		$ 300
Subsequent Event [Member] | Public Service Electric and Gas Company | Medium Term Notes Three Point One Five Percent due Two Thousand Fifty [Member]
Debt Instrument [Line Items]
Issuance of Long-Term Debt		$ 300

[1] Secured by essentially all property of PSE&G pursuant to its First and Refunding Mortgage.