Stock-Based Compensation (Financial Information For Other Equity Plans) (Details) - Other Equity Awards [Member] - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Employee service share-based compensation, aggregate disclosures
Compensation expense included in Entergy's net income	$ 10.8	$ 9.4
Tax benefit recognized in Entergy's net income	2.7	2.4
Compensation cost capitalized as part of fixed assets and inventory	$ 4.0	$ 3.4

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

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