Revenues Revenues (Details) $ in Millions		3 Months Ended				9 Months Ended
		Sep. 30, 2018 USD ($) $ / mwd MW	Sep. 30, 2017 USD ($)	Jun. 30, 2017 USD ($)	Mar. 31, 2017 USD ($)	Sep. 30, 2018 USD ($) $ / mwd MW	Sep. 30, 2017 USD ($)
Revenues [Line Items]
Lease Receivable adjustment				$ 22	$ 55	$ 20	$ 77
Revenue from Contract with Customers		$ 2,383	$ 2,043			6,989	6,278
Revenues Unrelated to Contracts with Customers	[1]	11	211			239	709
Total Operating Revenues		2,394	2,254			7,228	6,987
Electric Distribution Contracts [Member]
Revenues [Line Items]
Revenue from Contract with Customers		1,072	1,014			2,516	2,472
Gas Distribution [Member]
Revenues [Line Items]
Revenue from Contract with Customers		136	132			1,136	1,113
Electric Transmission [Member]
Revenues [Line Items]
Revenue from Contract with Customers		312	308			925	914
Electricity and Related Products [Member] | PJM [Member] | Third Party Sales [Member]
Revenues [Line Items]
Revenue from Contract with Customers		558	300			1,429	916
Electricity and Related Products [Member] | PJM [Member] | Sales to Affiliates [Member]
Revenues [Line Items]
Revenue from Contract with Customers		0	0			0	0
Electricity and Related Products [Member] | NY ISO [Member]
Revenues [Line Items]
Revenue from Contract with Customers		56	49			161	135
Electricity and Related Products [Member] | ISO New England [Member]
Revenues [Line Items]
Revenue from Contract with Customers		12	15			73	35
Gas Sales [Member] | Third Party Sales [Member]
Revenues [Line Items]
Revenue from Contract with Customers		24	26			118	89
Gas Sales [Member] | Sales to Affiliates [Member]
Revenues [Line Items]
Revenue from Contract with Customers		0	0			0	0
Other Revenues from Contracts with Customers [Member]
Revenues [Line Items]
Revenue from Contract with Customers	[2]	213	199			631	604
PSE And G [Member]
Revenues [Line Items]
Revenue from Contract with Customers		1,586	1,517			4,785	4,698
Revenues Unrelated to Contracts with Customers	[1]	9	13			41	51
Total Operating Revenues		1,595	1,530			4,826	4,749
PSE And G [Member] | Electric Distribution Contracts [Member]
Revenues [Line Items]
Revenue from Contract with Customers		1,072	1,014			2,516	2,472
PSE And G [Member] | Gas Distribution [Member]
Revenues [Line Items]
Revenue from Contract with Customers		142	136			1,149	1,124
PSE And G [Member] | Electric Transmission [Member]
Revenues [Line Items]
Revenue from Contract with Customers		312	308			925	914
PSE And G [Member] | Electricity and Related Products [Member] | PJM [Member] | Third Party Sales [Member]
Revenues [Line Items]
Revenue from Contract with Customers		0	0			0	0
PSE And G [Member] | Electricity and Related Products [Member] | PJM [Member] | Sales to Affiliates [Member]
Revenues [Line Items]
Revenue from Contract with Customers		0	0			0	0
PSE And G [Member] | Electricity and Related Products [Member] | NY ISO [Member]
Revenues [Line Items]
Revenue from Contract with Customers		0	0			0	0
PSE And G [Member] | Electricity and Related Products [Member] | ISO New England [Member]
Revenues [Line Items]
Revenue from Contract with Customers		0	0			0	0
PSE And G [Member] | Gas Sales [Member] | Third Party Sales [Member]
Revenues [Line Items]
Revenue from Contract with Customers		0	0			0	0
PSE And G [Member] | Gas Sales [Member] | Sales to Affiliates [Member]
Revenues [Line Items]
Revenue from Contract with Customers		0	0			0	0
PSE And G [Member] | Other Revenues from Contracts with Customers [Member]
Revenues [Line Items]
Revenue from Contract with Customers	[2]	60	59			195	188
Power [Member]
Revenues [Line Items]
Revenue from Contract with Customers		875	653			2,857	2,323
Revenues Unrelated to Contracts with Customers	[1]	(7)	193			181	710
Total Operating Revenues		868	846			3,038	3,033
Anticipated Contract Revenues		$ 171				$ 171
Power [Member] | PJM [Member] | June 2018 to May 2019 [Member]
Revenues [Line Items]
Dollars Per Megawatt-Day | $ / mwd		205				205
Load (MW) | MW		9,200				9,200
Power [Member] | PJM [Member] | June 2019 to May 2020 [Member]
Revenues [Line Items]
Dollars Per Megawatt-Day | $ / mwd		116				116
Load (MW) | MW		8,900				8,900
Power [Member] | PJM [Member] | June 2020 to May 2021 [Member]
Revenues [Line Items]
Dollars Per Megawatt-Day | $ / mwd		170				170
Load (MW) | MW		8,100				8,100
Power [Member] | PJM [Member] | June 2021 to May 2022 [Member]
Revenues [Line Items]
Dollars Per Megawatt-Day | $ / mwd		178				178
Load (MW) | MW		7,700				7,700
Power [Member] | ISO New England [Member] | June 2017 to May 2018 [Member]
Revenues [Line Items]
Dollars Per Megawatt-Day | $ / mwd		231				231
Power [Member] | ISO New England [Member] | June 2018 to May 2019 [Member]
Revenues [Line Items]
Dollars Per Megawatt-Day | $ / mwd		314				314
Load (MW) | MW		820				820
Power [Member] | ISO New England [Member] | June 2019 to May 2020 [Member]
Revenues [Line Items]
Dollars Per Megawatt-Day | $ / mwd		231				231
Load (MW) | MW		1,330				1,330
Power [Member] | ISO New England [Member] | June 2020 to May 2021 [Member]
Revenues [Line Items]
Dollars Per Megawatt-Day | $ / mwd		195				195
Load (MW) | MW		1,330				1,330
Power [Member] | ISO New England [Member] | June 2021 to May 2022 [Member]
Revenues [Line Items]
Dollars Per Megawatt-Day | $ / mwd		192				192
Load (MW) | MW		950				950
Power [Member] | ISO New England [Member] | June 2022 to May 2023 [Member]
Revenues [Line Items]
Dollars Per Megawatt-Day | $ / mwd		231				231
Load (MW) | MW		480				480
Power [Member] | ISO New England [Member] | June 2023 to May 2024 [Member]
Revenues [Line Items]
Dollars Per Megawatt-Day | $ / mwd		231				231
Load (MW) | MW		480				480
Power [Member] | ISO New England [Member] | June 2024 to May 2025 [Member]
Revenues [Line Items]
Dollars Per Megawatt-Day | $ / mwd		231				231
Load (MW) | MW		480				480
Power [Member] | ISO New England [Member] | June 2025 to May 2026 [Member]
Revenues [Line Items]
Dollars Per Megawatt-Day | $ / mwd		231				231
Load (MW) | MW		480				480
Power [Member] | Electric Distribution Contracts [Member]
Revenues [Line Items]
Revenue from Contract with Customers		$ 0	0			$ 0	0
Power [Member] | Gas Distribution [Member]
Revenues [Line Items]
Revenue from Contract with Customers		0	0			0	0
Power [Member] | Electric Transmission [Member]
Revenues [Line Items]
Revenue from Contract with Customers		0	0			0	0
Power [Member] | Electricity and Related Products [Member] | PJM [Member] | Third Party Sales [Member]
Revenues [Line Items]
Revenue from Contract with Customers		558	300			1,429	916
Power [Member] | Electricity and Related Products [Member] | PJM [Member] | Sales to Affiliates [Member]
Revenues [Line Items]
Revenue from Contract with Customers		166	208			489	563
Power [Member] | Electricity and Related Products [Member] | NY ISO [Member]
Revenues [Line Items]
Revenue from Contract with Customers		56	49			161	135
Power [Member] | Electricity and Related Products [Member] | ISO New England [Member]
Revenues [Line Items]
Revenue from Contract with Customers		12	15			73	35
Power [Member] | Gas Sales [Member] | Third Party Sales [Member]
Revenues [Line Items]
Revenue from Contract with Customers		24	26			118	89
Power [Member] | Gas Sales [Member] | Sales to Affiliates [Member]
Revenues [Line Items]
Revenue from Contract with Customers		47	44			552	552
Power [Member] | Other Revenues from Contracts with Customers [Member]
Revenues [Line Items]
Revenue from Contract with Customers	[2]	12	11			35	33
Other [Member]
Revenues [Line Items]
Revenue from Contract with Customers		142	130			404	386
Revenues Unrelated to Contracts with Customers	[1]	9	5			17	(52)
Total Operating Revenues		151	135			421	334
Other [Member] | LIPA OSA contract fixed component [Member]
Revenues [Line Items]
Anticipated Contract Revenues		64				64
Other [Member] | Electric Distribution Contracts [Member]
Revenues [Line Items]
Revenue from Contract with Customers		0	0			0	0
Other [Member] | Gas Distribution [Member]
Revenues [Line Items]
Revenue from Contract with Customers		0	0			0	0
Other [Member] | Electric Transmission [Member]
Revenues [Line Items]
Revenue from Contract with Customers		0	0			0	0
Other [Member] | Electricity and Related Products [Member] | PJM [Member] | Third Party Sales [Member]
Revenues [Line Items]
Revenue from Contract with Customers		0	0			0	0
Other [Member] | Electricity and Related Products [Member] | PJM [Member] | Sales to Affiliates [Member]
Revenues [Line Items]
Revenue from Contract with Customers		0	0			0	0
Other [Member] | Electricity and Related Products [Member] | NY ISO [Member]
Revenues [Line Items]
Revenue from Contract with Customers		0	0			0	0
Other [Member] | Electricity and Related Products [Member] | ISO New England [Member]
Revenues [Line Items]
Revenue from Contract with Customers		0	0			0	0
Other [Member] | Gas Sales [Member] | Third Party Sales [Member]
Revenues [Line Items]
Revenue from Contract with Customers		0	0			0	0
Other [Member] | Gas Sales [Member] | Sales to Affiliates [Member]
Revenues [Line Items]
Revenue from Contract with Customers		0	0			0	0
Other [Member] | Other Revenues from Contracts with Customers [Member]
Revenues [Line Items]
Revenue from Contract with Customers	[2]	142	130			404	386
Other [Member] | LIPA OSA contract incentive component [Member]
Revenues [Line Items]
Anticipated Contract Revenues		10				10
Eliminations [Member]
Revenues [Line Items]
Revenue from Contract with Customers		(220)	(257)			(1,057)	(1,129)
Revenues Unrelated to Contracts with Customers	[1]	0	0			0	0
Total Operating Revenues		(220)	(257)			(1,057)	(1,129)
Eliminations [Member] | Electric Distribution Contracts [Member]
Revenues [Line Items]
Revenue from Contract with Customers		0	0			0	0
Eliminations [Member] | Gas Distribution [Member]
Revenues [Line Items]
Revenue from Contract with Customers		(6)	(4)			(13)	(11)
Eliminations [Member] | Electric Transmission [Member]
Revenues [Line Items]
Revenue from Contract with Customers		0	0			0	0
Eliminations [Member] | Electricity and Related Products [Member] | PJM [Member] | Third Party Sales [Member]
Revenues [Line Items]
Revenue from Contract with Customers		0	0			0	0
Eliminations [Member] | Electricity and Related Products [Member] | PJM [Member] | Sales to Affiliates [Member]
Revenues [Line Items]
Revenue from Contract with Customers		(166)	(208)			(489)	(563)
Eliminations [Member] | Electricity and Related Products [Member] | NY ISO [Member]
Revenues [Line Items]
Revenue from Contract with Customers		0	0			0	0
Eliminations [Member] | Electricity and Related Products [Member] | ISO New England [Member]
Revenues [Line Items]
Revenue from Contract with Customers		0	0			0	0
Eliminations [Member] | Gas Sales [Member] | Third Party Sales [Member]
Revenues [Line Items]
Revenue from Contract with Customers		0	0			0	0
Eliminations [Member] | Gas Sales [Member] | Sales to Affiliates [Member]
Revenues [Line Items]
Revenue from Contract with Customers		(47)	(44)			(552)	(552)
Eliminations [Member] | Other Revenues from Contracts with Customers [Member]
Revenues [Line Items]
Revenue from Contract with Customers	[2]	$ (1)	$ (1)			$ (3)	$ (3)

[1] Includes primarily alternative revenues at PSE&G, derivative contracts at Power, and lease contracts in Other. For the nine months ended September 30, 2018 and 2017, Other includes a $20 million loss and a $77 million loss, respectively, related to Energy Holdings’ investments in leases.

[2] Includes primarily revenues from appliance repair services at PSE&G, solar power projects and energy management and fuel service contracts with LIPA at Power, and PSEG LI’s OSA with LIPA in Other.