Stock-Based Compensation (Financial Information For Stock Options) (Details) - Employee Stock Option [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	$ 1.0	$ 1.0	$ 2.0	$ 2.0
Tax benefit recognized in Entergy's net income	0.2	0.2	0.5	0.5
Compensation cost capitalized as part of fixed assets and inventory	$ 0.4	$ 0.4	$ 0.8	$ 0.8