Stock-Based Compensation (Schedule Of Financial Information Of Options) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Employee Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested in Period, Fair Value	$ 5.0	$ 4.0	$ 6.0
Compensation expense included in Entergy's Consolidated Net Income for the year	3.8	4.3	4.4
Tax benefit (expense) recognized in Entergy's Consolidated Net Income for the year	1.0	1.1	1.7
Compensation cost capitalized as part of fixed assets and inventory	1.4	0.7	0.7
Restricted Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested in Period, Fair Value	25.0	25.0	24.0
Compensation expense included in Entergy's Consolidated Net Income for the year	20.2	19.8	19.7
Tax benefit (expense) recognized in Entergy's Consolidated Net Income for the year	5.1	5.1	7.6
Compensation cost capitalized as part of fixed assets and inventory	7.1	5.7	5.2
Long-Term Incentive Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense included in Entergy's Consolidated Net Income for the year	11.1	11.5	10.8
Tax benefit (expense) recognized in Entergy's Consolidated Net Income for the year	2.8	2.9	4.2
Compensation cost capitalized as part of fixed assets and inventory	4.0	3.3	3.0
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested in Period, Fair Value	6.0	3.0	0.4
Compensation expense included in Entergy's Consolidated Net Income for the year	2.2	2.9	2.5
Tax benefit (expense) recognized in Entergy's Consolidated Net Income for the year	0.6	0.7	1.0
Compensation cost capitalized as part of fixed assets and inventory	$ 0.9	$ 0.7	$ 0.6

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

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Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.

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