Retirement, Other Postretirement Benefits, And Defined Contribution Plans Schedule Of Amounts Recorded On The Balance Sheet (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Current liabilities	$ (61,815)	$ (66,184)
Non-current liabilities	(2,853,013)	(2,798,265)
Non-Qualified Pension Plans [Member]
Defined Benefit Plan, Accumulated Benefit Obligation	161,300	143,400
Accumulated other comprehensive income (before taxes)	16,700	24,900
Other Postretirement Benefits Plan [Member]
Employee contributions	37,176	38,640
Current liabilities	(38,963)	(48,040)
Non-current liabilities	(404,246)	(518,601)
Accumulated other comprehensive income (before taxes)	(59,216)	(37,901)
Entergy Arkansas [Member]
Non-current liabilities	(361,682)	(319,075)
Entergy Arkansas [Member] | Non-Qualified Pension Plans [Member]
Defined Benefit Plan, Accumulated Benefit Obligation	2,626	2,248
Current liabilities	(218)	(249)
Non-current liabilities	(2,979)	(2,506)
Total funded status	(3,197)	(2,755)
Assets for Plan Benefits, Defined Benefit Plan	1,535	1,232
Accumulated other comprehensive income (before taxes)	0
Entergy Arkansas [Member] | Other Postretirement Benefits Plan [Member]
Employee contributions	7,792	8,125
Current liabilities	0	0
Assets for Plan Benefits, Defined Benefit Plan	94,823	98,480
Accumulated other comprehensive income (before taxes)	0	0
Entergy Louisiana [Member]
Non-current liabilities	(692,728)	(677,619)
Entergy Louisiana [Member] | Non-Qualified Pension Plans [Member]
Defined Benefit Plan, Accumulated Benefit Obligation	1,802	1,682
Current liabilities	(193)	(216)
Non-current liabilities	(1,772)	(1,467)
Total funded status	(1,965)	(1,683)
Assets for Plan Benefits, Defined Benefit Plan	424	3
Accumulated other comprehensive income (before taxes)	18
Entergy Louisiana [Member] | Other Postretirement Benefits Plan [Member]
Employee contributions	8,269	8,876
Current liabilities	(15,580)	(18,467)
Non-current liabilities	(239,991)	(255,708)
Accumulated other comprehensive income (before taxes)	(37,792)	(29,654)
Defined Benefit Plan Regulatory Asset Before Tax	0	0
Entergy Mississippi [Member]
Non-current liabilities	(110,901)	(99,406)
Entergy Mississippi [Member] | Non-Qualified Pension Plans [Member]
Defined Benefit Plan, Accumulated Benefit Obligation	3,345	2,938
Current liabilities	(181)	(357)
Non-current liabilities	(3,671)	(2,930)
Total funded status	(3,852)	(3,287)
Assets for Plan Benefits, Defined Benefit Plan	1,757	1,432
Accumulated other comprehensive income (before taxes)	0
Entergy Mississippi [Member] | Other Postretirement Benefits Plan [Member]
Employee contributions	2,122	2,197
Current liabilities	0	0
Assets for Plan Benefits, Defined Benefit Plan	31,485	20,106
Accumulated other comprehensive income (before taxes)	0	0
Defined Benefit Plan Regulatory Asset Before Tax		164
Entergy New Orleans [Member] | Non-Qualified Pension Plans [Member]
Defined Benefit Plan, Accumulated Benefit Obligation	240	230
Current liabilities	(17)	(17)
Non-current liabilities	(230)	(215)
Total funded status	(247)	(232)
Liability, Defined Benefit Pension Plan	(558)	(559)
Accumulated other comprehensive income (before taxes)	0
Entergy New Orleans [Member] | Other Postretirement Benefits Plan [Member]
Employee contributions	1,123	1,343
Current liabilities	0	0
Assets for Plan Benefits, Defined Benefit Plan	71,027	55,398
Accumulated other comprehensive income (before taxes)	0	0
Entergy Texas [Member] | Non-Qualified Pension Plans [Member]
Defined Benefit Plan, Accumulated Benefit Obligation	7,949	7,391
Current liabilities	(633)	(723)
Non-current liabilities	(7,842)	(7,060)
Total funded status	(8,475)	(7,783)
Assets for Plan Benefits, Defined Benefit Plan	147
Liability, Defined Benefit Pension Plan		(603)
Accumulated other comprehensive income (before taxes)	0
Entergy Texas [Member] | Other Postretirement Benefits Plan [Member]
Employee contributions	2,456	2,602
Current liabilities	0	0
Assets for Plan Benefits, Defined Benefit Plan	99,863	67,068
Accumulated other comprehensive income (before taxes)	0	0
Defined Benefit Plan Regulatory Asset Before Tax		4,781
System Energy [Member]
Non-current liabilities	(125,412)	(109,816)
System Energy [Member] | Other Postretirement Benefits Plan [Member]
Employee contributions	1,732	1,765
Current liabilities	0	0
Assets for Plan Benefits, Defined Benefit Plan	4,918	1,123
Accumulated other comprehensive income (before taxes)	0	0
Defined Benefit Plan Regulatory Asset Before Tax	$ 1,064	$ 2,027