Decommissioning Trust Funds (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020	May 28, 2021
Decommissioning Trust Funds [Abstract]
Deferred taxes on unrealized gains/(losses) recorded in OCI for non-regulated decommissioning trusts	$ (27)	$ 10,812	$ (25,608)	$ 19,555
Amortized cost of debt securities	$ 1,954,000		$ 1,954,000		$ 2,423,000
Average coupon rate of debt securities	2.82%		2.82%
Average duration of debt securities, years			6 years 11 months 8 days
Average maturity of debt securities, years			10 years 9 months
Proceeds from the dispositions of debt securities	$ 273,000	276,000	$ 797,000	676,000
Gains from dispositions of debt securities, gross	6,000	15,000	17,000	29,000
Losses from dispositions of debt securities, gross	1,000	1,000	12,000	4,000
Debt Securities, Available-for-sale, Allowance for Credit Loss	200		200		100
Equity Securities, FV-NI, Unrealized Gain	228,000		389,000
Debt Securities [Member]
Decommissioning Trust Funds [Abstract]
Deferred taxes on unrealized gains/(losses) recorded in OCI for non-regulated decommissioning trusts			5,000		31,000
Entergy Arkansas [Member]
Decommissioning Trust Funds [Abstract]
Amortized cost of debt securities	$ 458,500		$ 458,500		420,400
Average coupon rate of debt securities	2.45%		2.45%
Average duration of debt securities, years			6 years 10 months 17 days
Average maturity of debt securities, years			8 years 1 month 20 days
Proceeds from the dispositions of debt securities	$ 12,300	17,700	$ 26,100	66,400
Gains from dispositions of debt securities, gross	700	1,300	1,600	5,800
Losses from dispositions of debt securities, gross	100	100	100	200
Equity Securities, FV-NI, Unrealized Gain	64,300		109,900
Entergy Louisiana [Member]
Decommissioning Trust Funds [Abstract]
Amortized cost of debt securities	$ 661,000		$ 661,000		581,400
Average coupon rate of debt securities	3.44%		3.44%
Average duration of debt securities, years			6 years 9 months 7 days
Average maturity of debt securities, years			12 years 3 months 25 days
Proceeds from the dispositions of debt securities	$ 62,500	34,100	$ 170,900	101,500
Gains from dispositions of debt securities, gross	1,500	2,000	4,800	4,900
Losses from dispositions of debt securities, gross	100	100	$ 3,300	700
Percentage Interest in River Bend			30.00%
Equity Securities, FV-NI, Unrealized Gain	92,900		$ 157,400
System Energy [Member]
Decommissioning Trust Funds [Abstract]
Amortized cost of debt securities	$ 450,900		$ 450,900		398,400
Average coupon rate of debt securities	2.43%		2.43%
Average duration of debt securities, years			7 years 3 months 7 days
Average maturity of debt securities, years			10 years 8 months 4 days
Proceeds from the dispositions of debt securities	$ 101,600	73,600	$ 175,700	165,600
Gains from dispositions of debt securities, gross	1,900	5,400	3,100	7,000
Losses from dispositions of debt securities, gross	200	$ 200	1,800	$ 400
Equity Securities, FV-NI, Unrealized Gain	60,600		103,300
Indian Point 3 [Member]
Decommissioning Trust Funds [Abstract]
Decommissioning Fund Investments, Fair Value					991,000
Indian Point 1 [Member]
Decommissioning Trust Funds [Abstract]
Decommissioning Fund Investments, Fair Value					631,000
Indian Point 2 [Member]
Decommissioning Trust Funds [Abstract]
Decommissioning Fund Investments, Fair Value					794,000
Palisades [Member]
Decommissioning Trust Funds [Abstract]
Decommissioning Fund Investments, Fair Value	$ 564,000		$ 564,000		$ 554,000
Entergy Wholesale Commodities [Member] | Indian Point Energy Center
Decommissioning Trust Funds [Abstract]
Decommissioning Fund Investments, Fair Value						$ 2,387,000