Trust Investments (Value Of Securities That Have Been In An Unrealized Loss Position For Less Than And Greater Than 12 Months) (Detail) - USD ($) $ in Millions		Sep. 30, 2018	Dec. 31, 2017
Nuclear Decommissioning Trust (NDT) Fund [Member] | Power [Member]
Schedule of Trust Investments [Line Items]
Continuous Unrealized Loss Position, Less Than 12 Months, Fair Value		$ 849	$ 603
Continuous Unrealized Loss Position, Less Than 12 Months, Gross Unrealized Losses		(42)	(8)
Continuous Unrealized Loss Position, Greater Than 12 Months, Fair Value		214	120
Continuous Unrealized Loss Position, Greater Than 12 Months, Gross Unrealized Losses		(11)	(3)
Rabbi Trust [Member]
Schedule of Trust Investments [Line Items]
Continuous Unrealized Loss Position, Less Than 12 Months, Fair Value		146	67
Continuous Unrealized Loss Position, Less Than 12 Months, Gross Unrealized Losses		(5)	(1)
Continuous Unrealized Loss Position, Greater Than 12 Months, Fair Value		42	34
Continuous Unrealized Loss Position, Greater Than 12 Months, Gross Unrealized Losses		(2)	(1)
Domestic Equity Securities [Member] | Nuclear Decommissioning Trust (NDT) Fund [Member] | Power [Member]
Schedule of Trust Investments [Line Items]
Continuous Unrealized Loss Position, Less Than 12 Months, Fair Value	[1]	78	40
Continuous Unrealized Loss Position, Less Than 12 Months, Gross Unrealized Losses	[1]	(7)	(2)
Continuous Unrealized Loss Position, Greater Than 12 Months, Fair Value	[1]	4	0
Continuous Unrealized Loss Position, Greater Than 12 Months, Gross Unrealized Losses	[1]	0	0
International Equity Securities [Member] | Nuclear Decommissioning Trust (NDT) Fund [Member] | Power [Member]
Schedule of Trust Investments [Line Items]
Continuous Unrealized Loss Position, Less Than 12 Months, Fair Value	[1]	87	29
Continuous Unrealized Loss Position, Less Than 12 Months, Gross Unrealized Losses	[1]	(14)	(3)
Continuous Unrealized Loss Position, Greater Than 12 Months, Fair Value	[1]	8	2
Continuous Unrealized Loss Position, Greater Than 12 Months, Gross Unrealized Losses	[1]	(2)	0
Equity Securities [Member] | Nuclear Decommissioning Trust (NDT) Fund [Member] | Power [Member]
Schedule of Trust Investments [Line Items]
Continuous Unrealized Loss Position, Less Than 12 Months, Fair Value	[1]	165	69
Continuous Unrealized Loss Position, Less Than 12 Months, Gross Unrealized Losses	[1]	(21)	(5)
Continuous Unrealized Loss Position, Greater Than 12 Months, Fair Value	[1]	12	2
Continuous Unrealized Loss Position, Greater Than 12 Months, Gross Unrealized Losses	[1]	(2)	0
Government Debt Securities [Member] | Nuclear Decommissioning Trust (NDT) Fund [Member] | Power [Member]
Schedule of Trust Investments [Line Items]
Continuous Unrealized Loss Position, Less Than 12 Months, Fair Value	[2]	342	343
Continuous Unrealized Loss Position, Less Than 12 Months, Gross Unrealized Losses	[2]	(10)	(2)
Continuous Unrealized Loss Position, Greater Than 12 Months, Fair Value	[2]	153	91
Continuous Unrealized Loss Position, Greater Than 12 Months, Gross Unrealized Losses	[2]	(7)	(2)
Government Debt Securities [Member] | Rabbi Trust [Member]
Schedule of Trust Investments [Line Items]
Continuous Unrealized Loss Position, Less Than 12 Months, Fair Value	[3]	70	28
Continuous Unrealized Loss Position, Less Than 12 Months, Gross Unrealized Losses	[3]	(2)	0
Continuous Unrealized Loss Position, Greater Than 12 Months, Fair Value	[3]	28	25
Continuous Unrealized Loss Position, Greater Than 12 Months, Gross Unrealized Losses	[3]	(2)	(1)
Corporate Debt Obligations [Member] | Nuclear Decommissioning Trust (NDT) Fund [Member] | Power [Member]
Schedule of Trust Investments [Line Items]
Continuous Unrealized Loss Position, Less Than 12 Months, Fair Value	[4]	342	191
Continuous Unrealized Loss Position, Less Than 12 Months, Gross Unrealized Losses	[4]	(11)	(1)
Continuous Unrealized Loss Position, Greater Than 12 Months, Fair Value	[4]	49	27
Continuous Unrealized Loss Position, Greater Than 12 Months, Gross Unrealized Losses	[4]	(2)	(1)
Corporate Debt Obligations [Member] | Rabbi Trust [Member]
Schedule of Trust Investments [Line Items]
Continuous Unrealized Loss Position, Less Than 12 Months, Fair Value	[5]	76	39
Continuous Unrealized Loss Position, Less Than 12 Months, Gross Unrealized Losses	[5]	(3)	(1)
Continuous Unrealized Loss Position, Greater Than 12 Months, Fair Value	[5]	14	9
Continuous Unrealized Loss Position, Greater Than 12 Months, Gross Unrealized Losses	[5]	0	0
Total Debt Securities [Member] | Nuclear Decommissioning Trust (NDT) Fund [Member] | Power [Member]
Schedule of Trust Investments [Line Items]
Continuous Unrealized Loss Position, Less Than 12 Months, Fair Value		684	534
Continuous Unrealized Loss Position, Less Than 12 Months, Gross Unrealized Losses		(21)	(3)
Continuous Unrealized Loss Position, Greater Than 12 Months, Fair Value		202	118
Continuous Unrealized Loss Position, Greater Than 12 Months, Gross Unrealized Losses		(9)	(3)
Total Debt Securities [Member] | Rabbi Trust [Member]
Schedule of Trust Investments [Line Items]
Continuous Unrealized Loss Position, Less Than 12 Months, Fair Value		146	67
Continuous Unrealized Loss Position, Less Than 12 Months, Gross Unrealized Losses		(5)	(1)
Continuous Unrealized Loss Position, Greater Than 12 Months, Fair Value		42	34
Continuous Unrealized Loss Position, Greater Than 12 Months, Gross Unrealized Losses		$ (2)	$ (1)

[1] Equity Securities—Investments in marketable equity securities within the NDT Fund are primarily in common stocks within a broad range of industries and sectors. Effective January 1, 2018, unrealized gains and losses on these securities are recorded in Net Income.

[2] Debt Securities (Government)—Unrealized gains and losses on these securities are recorded in Accumulated Other Comprehensive Income (Loss). The unrealized losses on Power’s NDT investments in U.S. Treasury obligations and Federal Agency mortgage-backed securities were caused by interest rate changes. These investments are guaranteed by the U.S. government or an agency of the U.S. government. Power also has investments in municipal bonds that are primarily in investment grade securities. It is not expected that these securities will settle for less than their amortized cost. Since Power does not intend to sell these securities nor will it be more-likely-than-not required to sell, Power does not consider these debt securities to be other-than-temporarily impaired as of September 30, 2018.

[3] Debt Securities (Government)—Unrealized gains and losses on these securities are recorded in Accumulated Other Comprehensive Income (Loss). The unrealized losses on PSEG’s Rabbi Trust investments in U.S. Treasury obligations and Federal Agency mortgage-backed securities were caused by interest rate changes. These investments are guaranteed by the U.S. government or an agency of the U.S. government. PSEG also has investments in municipal bonds that are primarily in investment grade securities. It is not expected that these securities will settle for less than their amortized cost. Since PSEG does not intend to sell these securities nor will it be more-likely-than-not required to sell, PSEG does not consider these debt securities to be other-than-temporarily impaired as of September 30, 2018.

[4] Debt Securities (Corporate)—Unrealized gains and losses on these securities are recorded in Accumulated Other Comprehensive Income (Loss). Power’s investments in corporate bonds are primarily in investment grade securities. It is not expected that these securities would settle for less than their amortized cost. Since Power does not intend to sell these securities nor will it be more-likely-than-not required to sell, Power does not consider these debt securities to be other-than-temporarily impaired as of September 30, 2018.

[5] Debt Securities (Corporate)—Unrealized gains and losses on these securities are recorded in Accumulated Other Comprehensive Income (Loss). PSEG’s investments in corporate bonds are primarily in investment grade securities. It is not expected that these securities would settle for less than their amortized cost. Since PSEG does not intend to sell these securities nor will it be more-likely-than-not required to sell, PSEG does not consider these debt securities to be other-than-temporarily impaired as of September 30, 2018.