Stock-Based Compensation (Financial Information For Other Equity Plans) (Details) - Other Equity Awards [Member] - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Employee service share-based compensation, aggregate disclosures
Compensation expense included in Entergy's net income	$ 9.7	$ 9.6	$ 20.5	$ 19.0
Tax benefit recognized in Entergy's net income	2.5	2.5	5.2	4.9
Compensation cost capitalized as part of fixed assets and inventory	$ 4.0	$ 3.8	$ 8.0	$ 7.2

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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