Income Taxes Income Taxes (Summary of Interest on Income Taxes Expense Related to Unrecognized Tax Benefits) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Unrecognized Tax Expense, Income Tax Penalties and Interest Expense	$ (2.0)		$ (4.0)
Entergy Arkansas [Member]
Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense	1.6	$ 0.4
Unrecognized Tax Expense, Income Tax Penalties and Interest Expense			(0.8)
Entergy Louisiana [Member]
Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense	0.4	0.3
Unrecognized Tax Expense, Income Tax Penalties and Interest Expense			(10.8)
Entergy Mississippi [Member]
Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense	0.7	0.5	0.2
Entergy New Orleans [Member]
Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense	1.2	1.3
Unrecognized Tax Expense, Income Tax Penalties and Interest Expense			(0.8)
Entergy Texas [Member]
Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense	0.0	0.2
Unrecognized Tax Expense, Income Tax Penalties and Interest Expense			(0.2)
System Energy [Member]
Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense		$ 0.2
Unrecognized Tax Expense, Income Tax Penalties and Interest Expense	$ (10.2)		$ (2.6)