Available-For-Sale Securities (Value Of Securities That Have Been In An Unrealized Loss Position For Less Than And Greater Than 12 Months) (Detail) (USD $) In Millions, unless otherwise specified	Mar. 31, 2015		Dec. 31, 2014
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	$ 31		$ 26
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	0		0
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer Aggregate Losses Accumulated in Investments	0		0
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months Aggregate Losses Accumulated in Investments	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	0	[1]	0	[1]
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	0	[1]	0	[1]
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer Aggregate Losses Accumulated in Investments	0	[1]	0	[1]
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months Aggregate Losses Accumulated in Investments	0	[1]	0	[1]
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	6	[2]	2	[2]
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	0	[2]	0	[2]
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer Aggregate Losses Accumulated in Investments	0	[2]	0	[2]
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months Aggregate Losses Accumulated in Investments	0	[2]	0	[2]
Rabbi Trust [Member] | Other 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	25	[3]	24	[3]
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	0	[3]	0	[3]
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer Aggregate Losses Accumulated in Investments	0	[3]	0	[3]
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months Aggregate Losses Accumulated in Investments	0	[3]	0	[3]
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	31		26
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	0		0
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer Aggregate Losses Accumulated in Investments	0		0
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months Aggregate Losses Accumulated in Investments	0		0
Nuclear Decommissioning Trust (NDT) Fund [Member] | Power [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	205		356
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	40		59
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer Aggregate Losses Accumulated in Investments	(2)		(3)
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months Aggregate Losses Accumulated in Investments	(9)		(9)
Nuclear Decommissioning Trust (NDT) Fund [Member] | Power [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	122	[4]	162	[4]
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	0	[4]	1	[4]
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer Aggregate Losses Accumulated in Investments	0	[4]	0	[4]
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months Aggregate Losses Accumulated in Investments	(8)	[4]	(8)	[4]
Nuclear Decommissioning Trust (NDT) Fund [Member] | Power [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	31	[5]	95	[5]
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	16	[5]	28	[5]
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer Aggregate Losses Accumulated in Investments	0	[5]	(1)	[5]
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months Aggregate Losses Accumulated in Investments	0	[5]	0	[5]
Nuclear Decommissioning Trust (NDT) Fund [Member] | Power [Member] | Other 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	52	[6]	99	[6]
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	24	[6]	30	[6]
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer Aggregate Losses Accumulated in Investments	(2)	[6]	(2)	[6]
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months Aggregate Losses Accumulated in Investments	(1)	[6]	(1)	[6]
Nuclear Decommissioning Trust (NDT) Fund [Member] | Power [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	83		194
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	40		58
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer Aggregate Losses Accumulated in Investments	(2)		(3)
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months Aggregate Losses Accumulated in Investments	$ (1)		$ (1)

[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 United States Treasury obligations and Federal Agency mortgage-backed securities were caused by interest rate changes. Since these investments are guaranteed by the United States government or an agency of the United States government, it is not expected that these securities will settle for less than their amortized cost basis, since PSEG does not intend to sell nor will it be more-likely-than-not required to sell. PSEG does not consider these securities to be other-than-temporarily impaired as of March 31, 2015.

[3] Debt Securities (Other)—PSEG’s investments in corporate bonds, collateralized mortgage obligations, asset-backed securities and municipal government obligations are limited to 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 March 31, 2015.

[4] 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 March 31, 2015.

[5] Debt Securities (Government)—Unrealized losses on Power’s NDT investments in United States Treasury obligations and Federal Agency mortgage-backed securities were caused by interest rate changes. Since these investments are guaranteed by the United States government or an agency of the United States government, it is not expected that these securities will settle for less than their amortized cost basis, since Power does not intend to sell nor will it be more-likely-than-not required to sell. Power does not consider these securities to be other-than-temporarily impaired as of March 31, 2015.

[6] Debt Securities (Other)—Power’s investments in corporate bonds, collateralized mortgage obligations, asset-backed securities and municipal government obligations are limited to 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 March 31, 2015.