Decommissioning Trust Funds (Fair Value Of Debt Securities By Contractual Maturities) (Details) - USD ($) $ in Millions	Dec. 31, 2022	Dec. 31, 2021
Fair value of debt securities by contractual maturities
Less than 1 year	$ 62.0	$ 0.0
1 year - 5 years	520.0	473.0
5 years - 10 years	461.0	655.0
10 years - 15 years	117.0	389.0
15 years - 20 years	161.0	130.0
20 years+	334.0	530.0
Total	1,655.0	2,177.0
Entergy Arkansas [Member]
Fair value of debt securities by contractual maturities
Less than 1 year	21.2	0.0
1 year - 5 years	159.7	91.7
5 years - 10 years	191.7	217.4
10 years - 15 years	38.0	146.0
15 years - 20 years	42.6	35.7
20 years+	17.5	35.5
Total	470.7	526.3
Entergy Louisiana [Member]
Fair value of debt securities by contractual maturities
Less than 1 year	33.6	0.0
1 year - 5 years	159.1	157.8
5 years - 10 years	161.7	173.0
10 years - 15 years	67.1	123.0
15 years - 20 years	83.3	80.2
20 years+	220.3	260.2
Total	725.1	794.2
System Energy [Member]
Fair value of debt securities by contractual maturities
Less than 1 year	6.8	0.0
1 year - 5 years	201.7	156.8
5 years - 10 years	107.1	161.8
10 years - 15 years	11.7	58.6
15 years - 20 years	35.0	1.9
20 years+	97.4	145.4
Total	$ 459.7	$ 524.5