Stock-Based Compensation (Financial Information For Other Equity Plans) (Details) - Other Equity Awards [Member] - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Employee service share-based compensation, aggregate disclosures
Compensation expense included in Entergy's net income	$ 8.9	$ 8.4	$ 27.9	$ 25.6
Tax benefit recognized in Entergy's net income	2.2	2.1	7.1	6.5
Compensation cost capitalized as part of fixed assets and inventory	$ 3.6	$ 3.0	$ 10.8	$ 8.8

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

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