Income Taxes (Narrative) (Details) - USD ($) $ / shares in Units, $ in Thousands		1 Months Ended				3 Months Ended								9 Months Ended		12 Months Ended
	Jan. 01, 2018	Jun. 30, 2018	Oct. 31, 2015	Aug. 31, 2008	Jul. 31, 2008	Mar. 31, 2021	Dec. 31, 2020	Mar. 31, 2020	Dec. 31, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Dec. 31, 2015	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Jan. 01, 2021	Nov. 30, 2019	Jan. 01, 2019
Income Taxes [Line Items]
Valuation allowance on the deferred tax assets related to state net operating loss carryovers							$ 329,000		$ 303,000									$ 329,000	$ 303,000
Unrecognized tax benefits if recognized, would lower the effective income tax rates							2,208,000		2,421,000		$ 2,161,000							2,208,000	2,421,000	$ 2,161,000
Remaining balances of unrecognized tax benefits, effective income tax rates							3,491,000		4,962,000		5,020,000							3,491,000	4,962,000	5,020,000
Accrued income tax interest and penalties							44,000		48,000		44,000							44,000	48,000	44,000
Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense																		(4,000)	4,000	7,000
Deferred Income Taxes and Tax Credits																		(131,114)	193,950	$ (256,848)
Deferred Tax Assets, Valuation Allowance							328,581		303,307									328,581	303,307
Regulatory Liability, Noncurrent							2,323,851		1,961,005									2,323,851	1,961,005
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent	21.00%																			35.00%	35.00%
Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount																			24,000
Regulatory Liability For Income Taxes - Current and Non Current							1,600,000		1,700,000									1,600,000	1,700,000
Deferred tax asset operating loss carryforward EUHC re-consolidation															$ 41,000
Net operating loss carryforwards							1,580,109		1,133,197									1,580,109	1,133,197
Deferred Tax Assets, Net of Valuation Allowance							4,214,739		3,779,520									4,214,739	3,779,520
Increase (Reduction) in income tax resulting from Entergy Wholesale Commodities restructuring																		9,223	173,725	$ 0
Utility Restructuring Nuclear Decommissioning Liability Effect											165,000
Utility Restructuring State Income Tax Effect											5,000
Annual Limit on Deduction for Compensation of Certain Covered Employees	$ 1,000
Regulatory Liability For Income Taxes Net							1,521,757		1,633,159									1,521,757	1,633,159
Limit on Annual Net Operating Loss as a Percent of Annual Taxable Income	80.00%
Utility Restructuring											170,000							0	0	169,918
Discontinued Operation, Tax Effect of Discontinued Operation										$ 29,000
Permanent difference and income tax benefit			$ 334,000
Reduction in deferred income tax expense																		230,000
Increase in deferred income tax expense																		61,000
Miscellaneous tax benefits																		13,000
Adjustable taxable income limitation	30.00%																								50.00%
CARES Act Deferred Tax Expense																		64,000
Reduction in unrecognized tax benefits due to decommissioning liability in COGS							1,500,000											1,500,000
Increase to previously reported taxable income							190,000
Reduction in unrecognized tax benefits due to Vidalia purchased power decision							74,000
Permanent tax reduction due to stock compensation accounting rules								$ 24,700
Entergy Wholesale Commodities [Member]
Income Taxes [Line Items]
Deferred Income Taxes and Tax Credits																		105,000
Increase in deferred income tax expense																		105,000
Entergy Arkansas [Member]
Income Taxes [Line Items]
Unrecognized tax benefits if recognized, would lower the effective income tax rates							259,300		203,300		85,400							259,300	203,300	85,400
Accrued income tax interest and penalties							2,300		3,100		1,700							2,300	3,100	1,700
Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense																		(800)	1,400	200
Deferred Income Taxes and Tax Credits																		87,019	94,368	129,524
Regulatory Liability, Noncurrent							686,872		559,555									686,872	559,555
Regulatory Liability For Income Taxes - Current and Non Current														$ 21,000
Net operating loss carryforwards							119,555		112,658									119,555	112,658
Deferred Tax Assets, Net of Valuation Allowance							554,255		471,869									554,255	471,869
Noncash Capital Contribution from Parent											94,000									94,335
Change in accounting method for tax purposes, effect of change on taxable income											1,800,000
Accrued deductible temporary difference related to election to mark-to-market certain power purchase and sales agreements											2,100,000									2,100,000
Regulatory Liability For Income Taxes Net							467,031		478,174									467,031	478,174
State Effective Income Tax Rate, Percent														6.50%
Permanent tax reduction due to stock compensation accounting rules								4,800
Entergy Louisiana [Member]
Income Taxes [Line Items]
Unrecognized tax benefits if recognized, would lower the effective income tax rates							63,800		556,300		594,000							63,800	556,300	594,000
Accrued income tax interest and penalties							3,400		14,200		17,900							3,400	14,200	17,900
Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense																		(10,800)	(3,700)	3,800
Regulatory Liabilities									2,400										2,400
Deferred Income Taxes and Tax Credits																		(356,256)	196,533	174,063
Regulatory Liability, Noncurrent							918,293		794,140									918,293	794,140
Tax benefits related to Hurricane Katrina and Hurricane Rita contingent sharing obligation		$ 52,000
Net operating loss carryforwards							363,806		65,178									363,806	65,178
Deferred Tax Assets, Net of Valuation Allowance							700,307		618,692									700,307	618,692
Change in accounting method for tax purposes, effect of change on taxable income													$ 2,200,000
Deductible temporary difference related to election to mark-to-market certain power purchase and sales agreements																						$ 2,200,000
Regulatory Liability For Income Taxes Net							447,628		500,083									447,628	500,083
Reduction in deferred income tax expense																		383,000
Reduction to income tax expense due to method of accounting																		31,000
Regulatory charge due to prior regulatory settlement - gross																		33,000
Regulatory charge due to prior regulatory settlement - net of tax																		24,000
Increase (Reduction) in income tax resulting from Act 55 financing settlement								32,000
Reduction of income tax expense due reversal of UTPs								58,000
Regulatory charge due to LPSC Act 55 Financing Order - Gross								29,000
Regulatory charge due to LPSC Act 55 Financing Order - Net of Tax								21,000
Deferred tax liability due to decommissioning liability in COGS							60,000											60,000
Decommissioning liability in COGS							221,000											221,000
Reduction in unrecognized tax benefits due to decommissioning liability in COGS							1,100,000											1,100,000
Permanent tax reduction due to stock compensation accounting rules								8,600
Entergy Mississippi [Member]
Income Taxes [Line Items]
Unrecognized tax benefits if recognized, would lower the effective income tax rates							50,700		1,900		1,500							50,700	1,900	1,500
Accrued income tax interest and penalties							1,900		1,700		1,200							1,900	1,700	1,200
Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense																		200	500	200
Deferred Income Taxes and Tax Credits																		36,827	32,547	56,502
Regulatory Liability, Noncurrent							15,828		21,512									15,828	21,512
Net operating loss carryforwards							54,262		21,492									54,262	21,492
Deferred Tax Assets, Net of Valuation Allowance							131,887		92,959									131,887	92,959
Accrued deductible temporary difference related to election to mark-to-market certain power purchase and sales agreements											1,900,000									1,900,000
Regulatory Liability For Income Taxes Net							224,000		236,988									224,000	236,988
Permanent tax reduction due to stock compensation accounting rules								2,700
Entergy New Orleans [Member]
Income Taxes [Line Items]
Unrecognized tax benefits if recognized, would lower the effective income tax rates							203,500		242,700		246,200							203,500	242,700	246,200
Accrued income tax interest and penalties							3,900		4,700		2,700							3,900	4,700	2,700
Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense																		(800)	2,000	600
Deferred Income Taxes and Tax Credits																		3,938	21,350	24,548
Net operating loss carryforwards							26,564		5,056									26,564	5,056
Deferred Tax Assets, Net of Valuation Allowance							88,881		69,138									88,881	69,138
Reduction to income tax expense																		8,000
Deductible temporary difference related to election to mark-to-market certain power purchase and sales agreements																					$ 1,100,000
Regulatory Liability For Income Taxes Net							55,675		49,090									55,675	49,090
Permanent tax reduction due to stock compensation accounting rules								1,500
Entergy Texas [Member]
Income Taxes [Line Items]
Unrecognized tax benefits if recognized, would lower the effective income tax rates							6,100		5,700		5,100							6,100	5,700	5,100
Accrued income tax interest and penalties							900		1,100		900							900	1,100	900
Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense																		(200)	200	500
Deferred Income Taxes and Tax Credits																		36,033	20,143	(39,545)
Regulatory Liability, Noncurrent							32,297		42,085									32,297	42,085
Net operating loss carryforwards							53,052		0									53,052	0
Deferred Tax Assets, Net of Valuation Allowance							60,543		65,293									60,543	65,293
Deductible temporary difference related to election to mark-to-market certain power purchase and sales agreements																		2,500,000
Regulatory Liability For Income Taxes Net							175,594		225,980									175,594	225,980
Permanent tax reduction due to stock compensation accounting rules								2,700
System Energy [Member]
Income Taxes [Line Items]
Unrecognized tax benefits if recognized, would lower the effective income tax rates							500		0		0							500	0	0
Accrued income tax interest and penalties							11,900		14,500		13,200							11,900	14,500	13,200
Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense																		(2,600)	1,300	4,700
Deferred Income Taxes and Tax Credits																		(455,732)	95	24,040
Regulatory Liability, Noncurrent							665,396		533,415									665,396	533,415
Net operating loss carryforwards							0		0									0	0
Deferred Tax Assets, Net of Valuation Allowance							311,353		293,186									311,353	293,186
Change in accounting method for tax purposes, effect of change on taxable income													$ 1,200,000
Regulatory Liability For Income Taxes Net							151,829		142,845									151,829	142,845
Deferred tax liability due to decommissioning liability in COGS							26,000											26,000
Decommissioning liability in COGS							102,000											102,000
Federal and state taxes payable due to decommissioning liability in COGS							402,000											402,000
Reduction in unrecognized tax benefits due to decommissioning liability in COGS							461,000											461,000
Permanent tax reduction due to stock compensation accounting rules								$ 1,300
Entergy Wholesale Commodities [Member]
Income Taxes [Line Items]
Increase (Reduction) in income tax resulting from Entergy Wholesale Commodities restructuring							9,200		19,000
Reduction of Income Tax Expense, Net of Unrecognized Tax Benefits, Resulting From Tax Election												$ 107,000
Reduction to income tax expense									174,000
Tax Adjustments, Settlements, and Unusual Provisions												$ 23,000
Change in accounting method for tax purposes, effect of change on taxable income									18,000
Reduction in unrecognized tax benefits due to decommissioning liability in COGS																								$ 156,000
Hurricane Rita [Member] | Entergy Gulf States Louisiana [Member]
Income Taxes [Line Items]
Proceeds from LURC				$ 274,700
Proceed from loan by LCDA to corporation LURC				$ 274,700
Hurricane Rita [Member] | Entergy Louisiana [Member]
Income Taxes [Line Items]
Proceeds from LURC					$ 679,000
Proceed from loan by LCDA to corporation LURC					$ 679,000
Subsequent Event [Member]
Income Taxes [Line Items]
Percent of tax group's consolidated assets that consist of regulated utility property																							90.00%
CARES Act annual payroll tax installment due resulting from deferred tax payments																$ 32,000
Subsequent Event [Member] | Entergy Arkansas [Member]
Income Taxes [Line Items]
State Effective Income Tax Rate, Percent																5.90%	6.20%
Reduction to Effective Income Tax Rate At Combined Federal and State Income Tax Rate																0.50%
Refund to customers related to a reduction in tax rate						$ 7,500
Internal Restructuring Guaranteed Credits to Customers [Member]
Income Taxes [Line Items]
Regulatory Liability, Noncurrent							26,400		33,000		40,000							26,400	33,000	40,000
Regulatory Liability Net Of Tax											$ 30,000									$ 30,000
Internal Restructuring Guaranteed Credits to Customers [Member] | Entergy Arkansas [Member]
Income Taxes [Line Items]
Regulatory Liability, Noncurrent							$ 26,400		$ 33,000									$ 26,400	$ 33,000
Preferred Stock, Five Point Three Seven Five Percent, Series A [Member] | Entergy Texas [Member]
Income Taxes [Line Items]
Preferred Stock, Value, Issued															$ 35,000
Preferred Stock, Dividend Rate, Percentage															5.375%
Preferred Stock, Liquidation Preference Per Share							$ 25								$ 25			$ 25