Available-For-Sale Securities (Fair Values And Gross Unrealized Gains And Losses For The Securities) (Detail) - USD ($) $ in Millions		Dec. 31, 2017	Dec. 31, 2016
Rabbi Trust [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value		$ 67	$ 106
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss		1	4
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value		34	4
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss		1	0
Cost		227	209
Gross Unrealized Gains		6	12
Gross Unrealized Losses		(2)	(4)
Fair Value		231	217
Rabbi Trust [Member] | Domestic Equity Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	[1]	0	0
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	[1]	0	0
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	[1]	0	0
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	[1]	0	0
Cost		22	11
Gross Unrealized Gains		3	11
Gross Unrealized Losses		0	0
Fair Value		25	22
Rabbi Trust [Member] | International Equity Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	[1]	0	0
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	[1]	0	0
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	[1]	0	0
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	[1]	0	0
Cost		0	0
Gross Unrealized Gains		0	0
Gross Unrealized Losses		0	0
Fair Value		0	0
Rabbi Trust [Member] | Equity Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	[1]	0	0
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	[1]	0	0
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	[1]	0	0
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	[1]	0	0
Cost		22	11
Gross Unrealized Gains		3	11
Gross Unrealized Losses		0	0
Fair Value		25	22
Rabbi Trust [Member] | Government Obligations [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	[2]	28	60
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	[2]	0	2
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	[2]	25	1
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	[2]	1	0
Cost		85	105
Gross Unrealized Gains		1	0
Gross Unrealized Losses		(1)	(2)
Fair Value		85	103
Rabbi Trust [Member] | Corporate Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	[3]	39	46
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	[3]	1	2
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	[3]	9	3
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	[3]	0	0
Cost		118	92
Gross Unrealized Gains		2	1
Gross Unrealized Losses		(1)	(2)
Fair Value		119	91
Rabbi Trust [Member] | Total Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value		67	106
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss		1	4
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value		34	4
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss		1	0
Cost		203	197
Gross Unrealized Gains		3	1
Gross Unrealized Losses		(2)	(4)
Fair Value		204	194
Rabbi Trust [Member] | Other Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Cost		2	1
Gross Unrealized Gains		0	0
Gross Unrealized Losses		0	0
Fair Value		2	1
Power [Member] | Nuclear Decommissioning Trust (NDT) Fund [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value		603	535
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss		8	19
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value		120	27
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss		3	2
Cost		1,794	1,604
Gross Unrealized Gains		350	275
Gross Unrealized Losses		(11)	(21)
Fair Value		2,133	1,858	[4]
Power [Member] | Nuclear Decommissioning Trust (NDT) Fund [Member] | Domestic Equity Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	[5]	40	51
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	[5]	2	3
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	[5]	0	2
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	[5]	0	0
Cost		405	439
Gross Unrealized Gains		245	214
Gross Unrealized Losses		(2)	(3)
Fair Value		648	650
Power [Member] | Nuclear Decommissioning Trust (NDT) Fund [Member] | International Equity Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	[5]	29	69
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	[5]	3	7
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	[5]	2	6
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	[5]	0	1
Cost		311	266
Gross Unrealized Gains		99	49
Gross Unrealized Losses		(3)	(8)
Fair Value		407	307
Power [Member] | Nuclear Decommissioning Trust (NDT) Fund [Member] | Equity Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	[5]	69	120
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	[5]	5	10
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	[5]	2	8
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	[5]	0	1
Cost		716	705
Gross Unrealized Gains		344	263
Gross Unrealized Losses		(5)	(11)
Fair Value		1,055	957
Power [Member] | Nuclear Decommissioning Trust (NDT) Fund [Member] | Government Obligations [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	[6]	343	276
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	[6]	2	6
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	[6]	91	4
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	[6]	2	0
Cost		586	518
Gross Unrealized Gains		2	8
Gross Unrealized Losses		(4)	(6)
Fair Value		584	520
Power [Member] | Nuclear Decommissioning Trust (NDT) Fund [Member] | Corporate Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	[7]	191	139
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss	[7]	1	3
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	[7]	27	15
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	[7]	1	1
Cost		400	337
Gross Unrealized Gains		4	4
Gross Unrealized Losses		(2)	(4)
Fair Value		402	337
Power [Member] | Nuclear Decommissioning Trust (NDT) Fund [Member] | Total Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value		534	415
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss		3	9
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value		118	19
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss		3	1
Cost		986	855
Gross Unrealized Gains		6	12
Gross Unrealized Losses		(6)	(10)
Fair Value		986	857
Power [Member] | Nuclear Decommissioning Trust (NDT) Fund [Member] | Other Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Cost		92	44
Gross Unrealized Gains		0	0
Gross Unrealized Losses		0	0
Fair Value		92	44
Power [Member] | Rabbi Trust [Member]
Schedule of Available-for-sale Securities [Line Items]
Fair Value		$ 57	$ 53

[1] Equity Securities—Investments in marketable equity securities within the Rabbi Trust Fund are through a mutual fund which invests primarily in common stocks within a broad range of industries and sectors.

[2] Debt Securities (Government)—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 before recovery 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 December 31, 2017.

[3] Debt Securities (Corporate)—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 before recovery 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 December 31, 2017.

[4] The NDT available-for-sale securities table excludes cash of $1 million as of December 31, 2016, which is part of the NDT Fund.

[5] Equity Securities—Investments in marketable equity securities within the NDT Fund are primarily in common stocks within a broad range of industries and sectors. The unrealized losses are distributed over a broad range of securities with limited impairment durations. Power does not consider these securities to be other-than-temporarily impaired as of December 31, 2017.

[6] Debt Securities (Government)—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 before recovery 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 December 31, 2017.

[7] Debt Securities (Corporate)—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 before recovery 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 December 31, 2017.