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, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Employee service share-based compensation, aggregate disclosures
Compensation expense included in Entergy's net income	$ 8.5	$ 7.6	$ 26.0	$ 24.1
Tax benefit recognized in Entergy's net income	2.2	3.0	6.6	9.3
Compensation cost capitalized as part of fixed assets and inventory	$ 2.5	$ 2.1	$ 7.3	$ 6.3

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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Represents the compensation cost capitalized during the period arising from equity-based compensation arrangements (for example, shares of stock, units, 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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