Fair Value Measurements (Fair Value Of Debt) (Detail) - USD ($) $ in Millions		Mar. 31, 2020	Dec. 31, 2019
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-Term Debt, Carrying Amount		$ 15,705	$ 15,108
Long-Term Debt, Fair Value		16,758	16,723
Power - Recourse Debt [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-Term Debt, Carrying Amount	[1]	2,841	2,840
Long-Term Debt, Fair Value	[1]	2,766	3,137
Public Service Electric and Gas Company [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-Term Debt, Carrying Amount	[1]	10,423	9,827
Long-Term Debt, Fair Value	[1]	11,569	11,107
PSEG [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-Term Debt, Carrying Amount	[1],[2]	2,441	2,441
Long-Term Debt, Fair Value	[1],[2]	2,423	2,479
Variable Rate [Domain] | PSEG [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Floating Rate Term Loan		$ 700	$ 700

[1] Given that these bonds do not trade actively, the fair value amounts of taxable debt securities (primarily Level 2 measurements) are generally determined by a valuation model that is based on a conventional discounted cash flow methodology. The fair value amounts above do not represent the price at which the outstanding debt may be called for redemption by each issuer under their respective debt agreements.

[2] of March 31, 2020 and December 31, 2019. The fair values of the term loan debt (Level 2 measurement) approximate the carrying value because the interest payments are based on LIBOR rates that are reset monthly and the debt is redeemable at face value by PSEG at any time.