Financial Information By Business Segments (Financial Information By Business Segments) (Detail) - USD ($) $ in Millions		3 Months Ended												6 Months Ended		12 Months Ended
		Dec. 31, 2018		Sep. 30, 2018	Mar. 31, 2018		Dec. 31, 2017		Sep. 30, 2017	Jun. 30, 2017		Mar. 31, 2017		Jun. 30, 2018		Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Segment Reporting Information [Line Items]
Operating Revenues		$ 2,468		$ 2,394	$ 2,818		$ 2,107		$ 2,254	$ 2,142		$ 2,591		$ 2,016		$ 9,696	$ 9,094	$ 8,966
Depreciation and Amortization																1,158	1,986	1,476
Operating Income (Loss)		501	[1]	$ 554	$ 832	[1]	363	[1]	$ 693	$ 195	[1]	$ 178	[1]	$ 411	[1]	2,298	1,429	1,598
Income from Equity Method Investments																15	14	11
Interest Income																29	30	30
Interest Expense																(476)	(391)	(385)
Income (Loss) before Income Taxes																1,855	1,268	1,298
Income Tax Expense (Benefit)																417	(306)	411
Net Income (Loss)																1,438	1,574	887
Gross Additions to Long-Lived Assets																3,912	4,190	4,199
Total Assets		45,326					42,716									45,326	42,716	40,070
Investments in Equity Method Subsidiaries		86					87									86	87	102
Power [Member]
Segment Reporting Information [Line Items]
Operating Revenues																4,146	3,860	3,861
PSE&G [Member]
Segment Reporting Information [Line Items]
Operating Revenues																6,471	6,324	6,303
Other [Member]
Segment Reporting Information [Line Items]
Operating Revenues																571	466	370
Eliminations [Member]
Segment Reporting Information [Line Items]
Operating Revenues																(1,492)	(1,556)	(1,568)
Retained Earnings [Member]
Segment Reporting Information [Line Items]
Net Income (Loss)																1,438	1,574	887
Operating Segments [Member] | Power [Member]
Segment Reporting Information [Line Items]
Operating Revenues																4,146	3,860	3,861
Depreciation and Amortization																354	1,268	881
Operating Income (Loss)																596	(367)	17
Income from Equity Method Investments																15	14	11
Interest Income																5	3	4
Interest Expense																(76)	(50)	(84)
Income (Loss) before Income Taxes																431	(250)	(43)
Income Tax Expense (Benefit)																66	(729)	(61)
Net Income (Loss)																365	479	18
Gross Additions to Long-Lived Assets																996	1,231	1,343
Total Assets		12,594					12,418									12,594	12,418	12,193
Investments in Equity Method Subsidiaries		86					87									86	87	102
Operating Segments [Member] | PSE&G [Member]
Segment Reporting Information [Line Items]
Operating Revenues																6,471	6,324	6,303
Depreciation and Amortization																770	685	565
Operating Income (Loss)																1,606	1,760	1,629
Income from Equity Method Investments																0	0	0
Interest Income																21	24	24
Interest Expense																(333)	(303)	(289)
Income (Loss) before Income Taxes																1,411	1,536	1,404
Income Tax Expense (Benefit)																344	563	515
Net Income (Loss)																1,067	973	889
Gross Additions to Long-Lived Assets																2,896	2,919	2,816
Total Assets		31,109					28,554									31,109	28,554	26,288
Investments in Equity Method Subsidiaries		0					0									0	0	0
Operating Segments [Member] | Other [Member]
Segment Reporting Information [Line Items]
Operating Revenues	[2]															571	466	370
Depreciation and Amortization	[2]															34	33	30
Operating Income (Loss)	[2]															96	36	(48)
Income from Equity Method Investments	[2]															0	0	0
Interest Income	[2]															9	5	4
Interest Expense	[2]															(73)	(40)	(14)
Income (Loss) before Income Taxes	[2]															13	(18)	(63)
Income Tax Expense (Benefit)	[2]															7	(140)	(43)
Net Income (Loss)	[2]															6	122	(20)
Gross Additions to Long-Lived Assets	[2]															20	40	40
Total Assets	[2]	2,604					2,666									2,604	2,666	2,373
Investments in Equity Method Subsidiaries	[2]	0					0									0	0	0
Eliminations [Member]
Segment Reporting Information [Line Items]
Operating Revenues	[3]															(1,492)	(1,556)	(1,568)
Depreciation and Amortization	[3]															0	0	0
Operating Income (Loss)	[3]															0	0	0
Income from Equity Method Investments	[3]															0	0	0
Interest Income	[3]															(6)	(2)	(2)
Interest Expense	[3]															6	2	2
Income (Loss) before Income Taxes	[3]															0	0	0
Income Tax Expense (Benefit)	[3]															0	0	0
Net Income (Loss)	[3]															0		0
Gross Additions to Long-Lived Assets	[3]															0	0	0
Total Assets	[3]	(981)					(922)									(981)	(922)	(784)
Investments in Equity Method Subsidiaries	[3]	$ 0					$ 0									$ 0	$ 0	$ 0

[1] The increases in Operating Income at PSEG consolidated and Power in the first and second quarters of 2018 as compared to the same quarters in 2017 were primarily due to higher costs in 2017 related to closing the coal/gas Hudson and Mercer units, which were fully depreciated as of June 1, 2017. The increases in Operating Income at PSEG consolidated and Power in the fourth quarter 2018 as compared to the same quarter in 2017 were primarily due to lower MTM losses and a gain on the sale of the Hudson and Mercer units.The decreases in Net Income at PSEG consolidated and Power in the fourth quarter 2018 as compared to the same quarter in 2017 also reflected the impact of the one-time benefit recorded in December 2017 as a result of the remeasurement of deferred tax balances and the inclusion in 2018 of net unrealized losses on equity investments in the NDT Fund in accordance with new accounting guidance.

[2] Includes amounts applicable to Energy Holdings and PSEG LI, which are below the quantitative threshold for separate disclosure as reportable segments. Other also includes amounts applicable to PSEG (parent corporation) and Services.

[3] Intercompany eliminations primarily relate to intercompany transactions between PSE&G and Power. For a further discussion of the intercompany transactions between PSE&G and Power, see Note 25. Related-Party Transactions.