Equity (Narrative) (Details) - USD ($) $ / shares in Units, $ in Millions		1 Months Ended	3 Months Ended		6 Months Ended
	Jul. 30, 2021	Jun. 30, 2021	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	May 01, 2021	Apr. 30, 2021	Dec. 31, 2020
Equity [Abstract]
Stock Options Excluded From Diluted Common Shares Outstanding Calculation			1,000,000	500,000	1,000,000	500,000
Shares, Issued		265,468	265,468		265,468
Common stock dividend (in dollars per share)			$ 0.95	$ 0.93	$ 1.90	$ 1.86
Shares Issued, Price Per Share		$ 106.87	$ 106.87		$ 106.87
Equity Distribution Sales Agreement, Maximum Aggregate Gross Sales Price [Abstract]		$ 1,000.0	$ 1,000.0		$ 1,000.0
Forward Sale Agreement, Aggregate Compensation to Sales Agents [Abstract]
Common Stock, Shares Authorized		499,000,000	499,000,000		499,000,000		499,000,000	500,000,000	499,000,000
Preferred Stock, Shares Authorized		1,000,000	1,000,000		1,000,000		1,000,000		0
Equity Distribution Sales Agreement, Net Sales Price					$ 26.8
Equity Distribution Sales Agreement, Gross Sales Price					28.2
Equity Distribution Sales Agreement, Aggregate Compensation to Sales Agents					0.3
Equity Distribution Sales Agreement, General Issuance Costs					$ 1.1
Forward Sale Agreement, Equity Offering Shares		416,853	416,853		416,853
Forward Sale Agreement, Gross Sales Price		$ 45.0
Forward Sale Agreement, Aggregate Compensation to Sales Agents		$ 0.5
Stock Issued During Period, Shares, Treasury Stock Reissued					443,060
System Energy [Member]
Forward Sale Agreement, Aggregate Compensation to Sales Agents [Abstract]
Common Stock, Shares Authorized		1,000,000	1,000,000		1,000,000				1,000,000
Entergy Texas [Member]
Forward Sale Agreement, Aggregate Compensation to Sales Agents [Abstract]
Common Stock, Shares Authorized		200,000,000	200,000,000		200,000,000				200,000,000
Subsequent Event [Member]
Equity [Abstract]
Common stock dividend (in dollars per share)	$ 0.95