Rate Filings (Details) - PSE And G [Member] $ in Millions	1 Months Ended		3 Months Ended	12 Months Ended
	Apr. 30, 2018 USD ($)	Jan. 31, 2018 USD ($)	Mar. 31, 2018 USD ($)	Dec. 31, 2018	Dec. 31, 2017
Regulatory Assets And Liabilities [Line Items]
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent					35.00%
Proposed BGSS rate per therm			0.15
BGSS Revenue Reduction			$ 104
Transmission Formula Rate [Member]
Regulatory Assets And Liabilities [Line Items]
Public Utilities, Requested Rate Increase (Decrease), Amount		$ 148
Electric Distribution [Member]
Regulatory Assets And Liabilities [Line Items]
Public Utilities, Approved Rate Increase (Decrease), Amount			71
Gas Distribution [Member]
Regulatory Assets And Liabilities [Line Items]
Public Utilities, Approved Rate Increase (Decrease), Amount			43
Subsequent Event [Member]
Regulatory Assets And Liabilities [Line Items]
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent				21.00%
BGSS Revenue Reduction	$ 15
Subsequent Event [Member] | Gas Weather Normalization Deferral [Member]
Regulatory Assets And Liabilities [Line Items]
Public Utilities, Approved Rate Increase (Decrease), Amount	55
2016 to 2017 [Member] | Subsequent Event [Member] | Gas Weather Normalization Deferral [Member]
Regulatory Assets And Liabilities [Line Items]
Public Utilities, Approved Rate Increase (Decrease), Amount	31
2015 to 2016 [Member] | Subsequent Event [Member] | Gas Weather Normalization Deferral [Member]
Regulatory Assets And Liabilities [Line Items]
Public Utilities, Approved Rate Increase (Decrease), Amount	$ 24
Energy Strong program [Member] | Electric Distribution [Member]
Regulatory Assets And Liabilities [Line Items]
Public Utilities, Approved Rate Increase (Decrease), Amount			8
Solar or EE Recovery Charge (RRC) [Member] | Electric Distribution [Member]
Regulatory Assets And Liabilities [Line Items]
Public Utilities, Approved Rate Increase (Decrease), Amount			20
Solar or EE Recovery Charge (RRC) [Member] | Gas Distribution [Member]
Regulatory Assets And Liabilities [Line Items]
Public Utilities, Approved Rate Increase (Decrease), Amount			$ (1)