Recent Accounting Standards Recent Accounting Standards (Details) - USD ($) $ in Millions	3 Months Ended			9 Months Ended
	Mar. 31, 2019	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Jan. 01, 2018
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Cumulative Effect of Change on Equity or Net Assets						$ 342
Cumulative Effect of New Accounting Principle in Period of Adoption						176
PSE And G [Member] | Accounting Standard Update 2017-07 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, Quantification		$ 15		$ 44
Prior Period Reclassification Adjustment			$ (2)		$ (5)
Power [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cumulative Effect of New Accounting Principle in Period of Adoption						$ 175
Power [Member] | Accounting Standard Update 2017-07 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Prior Period Reclassification Adjustment			2		6
Operating Revenues [Member] | PSE And G [Member] | Accounting Standards Update 2014-09 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Prior Period Reclassification Adjustment			(21)		(60)
Operating Revenues [Member] | Power [Member] | Accounting Standards Update 2014-09 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Prior Period Reclassification Adjustment			(27)		(53)
Energy Costs [Member] | PSE And G [Member] | Accounting Standards Update 2014-09 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Prior Period Reclassification Adjustment			(8)		(33)
Operation and Maintenance Expense [Member] | PSE And G [Member] | Accounting Standards Update 2014-09 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Prior Period Reclassification Adjustment			$ (13)		$ (27)
Maximum [Member] | Subsequent Event [Member] | Accounting Standards Update 2016-02 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, Quantification	$ 300
Maximum [Member] | Subsequent Event [Member] | PSE And G [Member] | Accounting Standards Update 2016-02 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, Quantification	100
Maximum [Member] | Subsequent Event [Member] | Power [Member] | Accounting Standards Update 2016-02 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, Quantification	$ 60