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Risk Management and Fair Values (Assets And Liabilities At Fair Value On A Recurring Basis) (Details) (USD $) In Millions, unless otherwise specified | Mar. 31, 2014 | Dec. 31, 2013
--- | --- | ---
Assets at fair value on a recurring basis |  |  |  |
Assets other than temporary cash investments | $ 4,991.0 |  | $ 4,903.0 |
Fair Value, Measurements, Recurring [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Temporary cash investments | 800.0 |  | 609.0 |
Total | 6,013.0 |  | 6.0 |
Liabilities at fair value on a recurring basis |  |  |  |
Total |  |  | 207 |
Power Contracts Liabilities [Member] | Fair Value, Measurements, Recurring [Member] |  |  |  |
Liabilities at fair value on a recurring basis |  |  |  |
Liabilities, Fair Value Disclosure on Recurring Basis | 110.0 |  | 5,787.0 |
Equity Securities [Member] | Fair Value, Measurements, Recurring [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Assets other than temporary cash investments | 3,061.0 | [1] | 3,073.0 | [1]
Debt Securities [Member] | Fair Value, Measurements, Recurring [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Assets other than temporary cash investments | 1,930.0 | [1] | 1,830.0 | [1]
Power Contracts Assets [Member] | Fair Value, Measurements, Recurring [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Assets other than temporary cash investments | 24.0 |  | 74.0 |
Securitization Recovery Trust Account [Member] | Fair Value, Measurements, Recurring [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Assets other than temporary cash investments | 48.0 |  | 46.0 |
Storm Reserve Escrow Account [Member] | Fair Value, Measurements, Recurring [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Assets other than temporary cash investments | 117.0 |  | 115.0 |
Gas Hedge Contracts Assets [Member] | Fair Value, Measurements, Recurring [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Assets other than temporary cash investments | 8.0 |  |  |
Fixed Transmission Rights (FTRs) [Member] | Fair Value, Measurements, Recurring [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Assets other than temporary cash investments | 25.0 |  | 34.0 |
Fair Value Inputs Level 1 [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Temporary cash investments | 800.0 |  | 609.0 |
Total | 2,153.0 |  | 6.0 |
Liabilities at fair value on a recurring basis |  |  |  |
Total |  |  | 0 |
Fair Value Inputs Level 1 [Member] | Power Contracts Liabilities [Member] |  |  |  |
Liabilities at fair value on a recurring basis |  |  |  |
Liabilities, Fair Value Disclosure on Recurring Basis | 0 |  | 2,031.0 |
Fair Value Inputs Level 1 [Member] | Equity Securities [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Assets other than temporary cash investments | 417.0 | [1] | 472.0 | [1]
Fair Value Inputs Level 1 [Member] | Debt Securities [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Assets other than temporary cash investments | 763.0 | [1] | 783.0 | [1]
Fair Value Inputs Level 1 [Member] | Power Contracts Assets [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Assets other than temporary cash investments | 0 |  | 0 |
Fair Value Inputs Level 1 [Member] | Securitization Recovery Trust Account [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Assets other than temporary cash investments | 48.0 |  | 46.0 |
Fair Value Inputs Level 1 [Member] | Storm Reserve Escrow Account [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Assets other than temporary cash investments | 117.0 |  | 115.0 |
Fair Value Inputs Level 1 [Member] | Gas Hedge Contracts Assets [Member] | Fair Value, Measurements, Recurring [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Assets other than temporary cash investments | 8.0 |  |  |
Fair Value Inputs Level 1 [Member] | Fixed Transmission Rights (FTRs) [Member] | Fair Value, Measurements, Recurring [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Assets other than temporary cash investments | 0 |  | 0 |
Fair Value Inputs Level 2 [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Temporary cash investments | 0 |  | 0 |
Total | 3,811.0 |  | 0 |
Liabilities at fair value on a recurring basis |  |  |  |
Total |  |  | 0 |
Fair Value Inputs Level 2 [Member] | Power Contracts Liabilities [Member] |  |  |  |
Liabilities at fair value on a recurring basis |  |  |  |
Liabilities, Fair Value Disclosure on Recurring Basis | 0 |  | 3,648.0 |
Fair Value Inputs Level 2 [Member] | Equity Securities [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Assets other than temporary cash investments | 2,644.0 | [1],[2] | 2,601.0 | [1],[2]
Fair Value Inputs Level 2 [Member] | Debt Securities [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Assets other than temporary cash investments | 1,167.0 | [1] | 1,047.0 | [1]
Fair Value Inputs Level 2 [Member] | Power Contracts Assets [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Assets other than temporary cash investments | 0 |  | 0 |
Fair Value Inputs Level 2 [Member] | Securitization Recovery Trust Account [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Assets other than temporary cash investments | 0 |  | 0 |
Fair Value Inputs Level 2 [Member] | Storm Reserve Escrow Account [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Assets other than temporary cash investments | 0 |  | 0 |
Fair Value Inputs Level 2 [Member] | Gas Hedge Contracts Assets [Member] | Fair Value, Measurements, Recurring [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Assets other than temporary cash investments | 0 |  |  |
Fair Value Inputs Level 2 [Member] | Fixed Transmission Rights (FTRs) [Member] | Fair Value, Measurements, Recurring [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Assets other than temporary cash investments | 0 |  | 0 |
Fair Value Inputs Level 3 [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Temporary cash investments | 0 |  | 0 |
Total | 49.0 |  | 0 |
Liabilities at fair value on a recurring basis |  |  |  |
Total |  |  | 207 |
Fair Value Inputs Level 3 [Member] | Power Contracts Liabilities [Member] |  |  |  |
Liabilities at fair value on a recurring basis |  |  |  |
Liabilities, Fair Value Disclosure on Recurring Basis | 110.0 |  | 108.0 |
Fair Value Inputs Level 3 [Member] | Equity Securities [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Assets other than temporary cash investments | 0 |  | 0 |
Fair Value Inputs Level 3 [Member] | Debt Securities [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Assets other than temporary cash investments | 0 |  | 0 |
Fair Value Inputs Level 3 [Member] | Power Contracts Assets [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Assets other than temporary cash investments | 24.0 |  | 74.0 |
Fair Value Inputs Level 3 [Member] | Securitization Recovery Trust Account [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Assets other than temporary cash investments | 0 |  | 0 |
Fair Value Inputs Level 3 [Member] | Storm Reserve Escrow Account [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Assets other than temporary cash investments | 0 |  | 0 |
Fair Value Inputs Level 3 [Member] | Gas Hedge Contracts Assets [Member] | Fair Value, Measurements, Recurring [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Assets other than temporary cash investments | 0 |  |  |
Fair Value Inputs Level 3 [Member] | Fixed Transmission Rights (FTRs) [Member] | Fair Value, Measurements, Recurring [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Assets other than temporary cash investments | 25.0 |  | 34.0 |
Entergy Arkansas [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Temporary cash investments | 216.1 |  | 122.8 |
Assets other than temporary cash investments | 721.5 |  | 710.9 |
Total | 974.4 |  | 863.5 |
Entergy Arkansas [Member] | Equity Securities [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Assets other than temporary cash investments | 460.8 | [1] | 463.3 | [1]
Entergy Arkansas [Member] | Debt Securities [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Assets other than temporary cash investments | 260.7 | [1] | 247.6 | [1]
Entergy Arkansas [Member] | Securitization Recovery Trust Account [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Assets other than temporary cash investments | 8.1 |  | 3.8 |
Entergy Arkansas [Member] | Storm Reserve Escrow Account [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Assets other than temporary cash investments | 26.0 |  | 26.0 |
Entergy Arkansas [Member] | Fixed Transmission Rights (FTRs) [Member] | Fair Value, Measurements, Recurring [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Assets other than temporary cash investments | 2.7 |  |  |
Entergy Arkansas [Member] | Fair Value Inputs Level 1 [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Temporary cash investments | 216.1 |  | 122.8 |
Total | 304.7 |  | 224.8 |
Entergy Arkansas [Member] | Fair Value Inputs Level 1 [Member] | Equity Securities [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Assets other than temporary cash investments | 3.7 | [1] | 13.6 | [1]
Entergy Arkansas [Member] | Fair Value Inputs Level 1 [Member] | Debt Securities [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Assets other than temporary cash investments | 50.8 | [1] | 58.6 | [1]
Entergy Arkansas [Member] | Fair Value Inputs Level 1 [Member] | Securitization Recovery Trust Account [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Assets other than temporary cash investments | 8.1 |  | 3.8 |
Entergy Arkansas [Member] | Fair Value Inputs Level 1 [Member] | Storm Reserve Escrow Account [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Assets other than temporary cash investments | 26.0 |  | 26.0 |
Entergy Arkansas [Member] | Fair Value Inputs Level 2 [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Total | 667.0 |  | 638.7 |
Entergy Arkansas [Member] | Fair Value Inputs Level 2 [Member] | Equity Securities [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Assets other than temporary cash investments | 457.1 | [1] | 449.7 | [1]
Entergy Arkansas [Member] | Fair Value Inputs Level 2 [Member] | Debt Securities [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Assets other than temporary cash investments | 209.9 | [1] | 189.0 | [1]
Entergy Arkansas [Member] | Fair Value Inputs Level 3 [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Total | 2.7 |  |  |
Entergy Arkansas [Member] | Fair Value Inputs Level 3 [Member] | Fixed Transmission Rights (FTRs) [Member] | Fair Value, Measurements, Recurring [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Assets other than temporary cash investments | 2.7 |  |  |
Entergy Gulf States Louisiana [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Temporary cash investments | 15.0 |  | 13.8 |
Assets other than temporary cash investments | 586.2 |  | 573.7 |
Total | 631.1 |  | 2.2 |
Entergy Gulf States Louisiana [Member] | Gas Hedge Contracts [Member] |  |  |  |
Liabilities at fair value on a recurring basis |  |  |  |
Liabilities, Fair Value Disclosure on Recurring Basis |  |  | 617.9 |
Entergy Gulf States Louisiana [Member] | Equity Securities [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Assets other than temporary cash investments | 359.9 | [1] | 370.8 | [1]
Entergy Gulf States Louisiana [Member] | Debt Securities [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Assets other than temporary cash investments | 226.3 | [1] | 202.9 | [1]
Entergy Gulf States Louisiana [Member] | Storm Reserve Escrow Account [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Assets other than temporary cash investments | 21.5 |  | 21.5 |
Entergy Gulf States Louisiana [Member] | Gas Hedge Contracts Assets [Member] | Fair Value, Measurements, Recurring [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Assets other than temporary cash investments | 3.0 |  |  |
Entergy Gulf States Louisiana [Member] | Fixed Transmission Rights (FTRs) [Member] | Fair Value, Measurements, Recurring [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Assets other than temporary cash investments | 5.4 |  | 6.7 |
Entergy Gulf States Louisiana [Member] | Fair Value Inputs Level 1 [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Temporary cash investments | 15.0 |  | 13.8 |
Total | 123.6 |  | 2.2 |
Entergy Gulf States Louisiana [Member] | Fair Value Inputs Level 1 [Member] | Gas Hedge Contracts [Member] |  |  |  |
Liabilities at fair value on a recurring basis |  |  |  |
Liabilities, Fair Value Disclosure on Recurring Basis |  |  | 136.8 |
Entergy Gulf States Louisiana [Member] | Fair Value Inputs Level 1 [Member] | Equity Securities [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Assets other than temporary cash investments | 11.0 | [1] | 27.6 | [1]
Entergy Gulf States Louisiana [Member] | Fair Value Inputs Level 1 [Member] | Debt Securities [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Assets other than temporary cash investments | 73.1 | [1] | 71.7 | [1]
Entergy Gulf States Louisiana [Member] | Fair Value Inputs Level 1 [Member] | Storm Reserve Escrow Account [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Assets other than temporary cash investments | 21.5 |  | 21.5 |
Entergy Gulf States Louisiana [Member] | Fair Value Inputs Level 1 [Member] | Gas Hedge Contracts Assets [Member] | Fair Value, Measurements, Recurring [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Assets other than temporary cash investments | 3.0 |  |  |
Entergy Gulf States Louisiana [Member] | Fair Value Inputs Level 2 [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Total | 502.1 |  | 0 |
Entergy Gulf States Louisiana [Member] | Fair Value Inputs Level 2 [Member] | Fair Value, Measurements, Recurring [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Total |  |  | 474.4 |
Entergy Gulf States Louisiana [Member] | Fair Value Inputs Level 2 [Member] | Equity Securities [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Assets other than temporary cash investments | 348.9 | [1] | 343.2 | [1]
Entergy Gulf States Louisiana [Member] | Fair Value Inputs Level 2 [Member] | Debt Securities [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Assets other than temporary cash investments | 153.2 | [1] | 131.2 | [1]
Entergy Gulf States Louisiana [Member] | Fair Value Inputs Level 3 [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Total | 5.4 |  |  |
Entergy Gulf States Louisiana [Member] | Fair Value Inputs Level 3 [Member] | Fair Value, Measurements, Recurring [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Total |  |  | 6.7 |
Entergy Gulf States Louisiana [Member] | Fair Value Inputs Level 3 [Member] | Fixed Transmission Rights (FTRs) [Member] | Fair Value, Measurements, Recurring [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Assets other than temporary cash investments | 5.4 |  | 6.7 |
Entergy Louisiana [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Temporary cash investments | 72.0 |  | 123.6 |
Assets other than temporary cash investments | 353.6 |  | 347.3 |
Total |  |  | 5.7 |
Entergy Louisiana [Member] | Fair Value, Measurements, Recurring [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Total | 442.5 |  | 484.0 |
Entergy Louisiana [Member] | Equity Securities [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Assets other than temporary cash investments | 225.0 | [1] | 224.2 | [1]
Entergy Louisiana [Member] | Debt Securities [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Assets other than temporary cash investments | 128.6 | [1] | 123.1 | [1]
Entergy Louisiana [Member] | Securitization Recovery Trust Account [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Assets other than temporary cash investments | 10.2 |  | 4.5 |
Entergy Louisiana [Member] | Storm Reserve Escrow Account [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Assets other than temporary cash investments | 3.7 |  | 2.9 |
Entergy Louisiana [Member] | Fixed Transmission Rights (FTRs) [Member] | Fair Value, Measurements, Recurring [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Assets other than temporary cash investments | 3.0 |  |  |
Entergy Louisiana [Member] | Fair Value Inputs Level 1 [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Temporary cash investments | 72.0 |  | 123.6 |
Total | 157.3 |  |  |
Entergy Louisiana [Member] | Fair Value Inputs Level 1 [Member] | Fair Value, Measurements, Recurring [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Total |  |  | 206.2 |
Entergy Louisiana [Member] | Fair Value Inputs Level 1 [Member] | Equity Securities [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Assets other than temporary cash investments | 11.1 | [1] | 13.5 | [1]
Entergy Louisiana [Member] | Fair Value Inputs Level 1 [Member] | Debt Securities [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Assets other than temporary cash investments | 60.3 | [1] | 61.7 | [1]
Entergy Louisiana [Member] | Fair Value Inputs Level 1 [Member] | Securitization Recovery Trust Account [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Assets other than temporary cash investments | 10.2 |  | 4.5 |
Entergy Louisiana [Member] | Fair Value Inputs Level 1 [Member] | Storm Reserve Escrow Account [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Assets other than temporary cash investments | 3.7 |  | 2.9 |
Entergy Louisiana [Member] | Fair Value Inputs Level 2 [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Total | 282.2 |  |  |
Entergy Louisiana [Member] | Fair Value Inputs Level 2 [Member] | Fair Value, Measurements, Recurring [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Total |  |  | 272.1 |
Entergy Louisiana [Member] | Fair Value Inputs Level 2 [Member] | Equity Securities [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Assets other than temporary cash investments | 213.9 | [1] | 210.7 | [1]
Entergy Louisiana [Member] | Fair Value Inputs Level 2 [Member] | Debt Securities [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Assets other than temporary cash investments | 68.3 | [1] | 61.4 | [1]
Entergy Louisiana [Member] | Fair Value Inputs Level 3 [Member] | Fair Value, Measurements, Recurring [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Total | 3.0 |  | 5.7 |
Entergy Louisiana [Member] | Fair Value Inputs Level 3 [Member] | Fixed Transmission Rights (FTRs) [Member] | Fair Value, Measurements, Recurring [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Assets other than temporary cash investments | 3.0 |  | 5.7 |
Entergy Mississippi [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Temporary cash investments | 70.3 |  | 51.8 |
Total |  |  | 53.5 |
Entergy Mississippi [Member] | Fair Value, Measurements, Recurring [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Total | 128.3 |  |  |
Entergy Mississippi [Member] | Storm Reserve Escrow Account [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Assets other than temporary cash investments | 51.8 |  | 0.7 |
Entergy Mississippi [Member] | Gas Hedge Contracts Assets [Member] | Fair Value, Measurements, Recurring [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Assets other than temporary cash investments | 1.4 |  |  |
Entergy Mississippi [Member] | Fixed Transmission Rights (FTRs) [Member] | Fair Value, Measurements, Recurring [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Assets other than temporary cash investments | 4.8 |  | 1.0 |
Entergy Mississippi [Member] | Fair Value Inputs Level 1 [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Temporary cash investments | 70.3 |  | 51.8 |
Total |  |  | 52.5 |
Entergy Mississippi [Member] | Fair Value Inputs Level 1 [Member] | Fair Value, Measurements, Recurring [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Total | 123.5 |  |  |
Entergy Mississippi [Member] | Fair Value Inputs Level 1 [Member] | Storm Reserve Escrow Account [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Assets other than temporary cash investments | 51.8 |  | 0.7 |
Entergy Mississippi [Member] | Fair Value Inputs Level 1 [Member] | Gas Hedge Contracts Assets [Member] | Fair Value, Measurements, Recurring [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Assets other than temporary cash investments | 1.4 |  |  |
Entergy Mississippi [Member] | Fair Value Inputs Level 3 [Member] | Fair Value, Measurements, Recurring [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Assets other than temporary cash investments | 4.8 |  | 1.0 |
Entergy Mississippi [Member] | Fair Value Inputs Level 3 [Member] | Fixed Transmission Rights (FTRs) [Member] | Fair Value, Measurements, Recurring [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Assets other than temporary cash investments | 4.8 |  | 1.0 |
Entergy New Orleans [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Temporary cash investments | 24.7 |  | 33.2 |
Total | 38.1 |  | 45.8 |
Entergy New Orleans [Member] | Storm Reserve Escrow Account [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Assets other than temporary cash investments | 12.4 |  | 10.5 |
Entergy New Orleans [Member] | Gas Hedge Contracts Assets [Member] | Fair Value, Measurements, Recurring [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Assets other than temporary cash investments |  |  | 0.1 |
Entergy New Orleans [Member] | Fixed Transmission Rights (FTRs) [Member] | Fair Value, Measurements, Recurring [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Assets other than temporary cash investments | 1.0 |  | 2.0 |
Entergy New Orleans [Member] | Fair Value Inputs Level 1 [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Temporary cash investments | 24.7 |  | 33.2 |
Total | 37.1 |  | 43.8 |
Entergy New Orleans [Member] | Fair Value Inputs Level 1 [Member] | Storm Reserve Escrow Account [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Assets other than temporary cash investments | 12.4 |  | 10.5 |
Entergy New Orleans [Member] | Fair Value Inputs Level 1 [Member] | Gas Hedge Contracts Assets [Member] | Fair Value, Measurements, Recurring [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Assets other than temporary cash investments |  |  | 0.1 |
Entergy New Orleans [Member] | Fair Value Inputs Level 3 [Member] | Fair Value, Measurements, Recurring [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Assets other than temporary cash investments | 1.0 |  | 2.0 |
Entergy New Orleans [Member] | Fair Value Inputs Level 3 [Member] | Fixed Transmission Rights (FTRs) [Member] | Fair Value, Measurements, Recurring [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Assets other than temporary cash investments | 1.0 |  | 2.0 |
Entergy Texas [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Temporary cash investments |  |  | 44.1 |
Total | 37.1 |  | 100.0 |
Entergy Texas [Member] | Securitization Recovery Trust Account [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Assets other than temporary cash investments | 29.7 |  | 37.5 |
Entergy Texas [Member] | Fair Value Inputs Level 1 [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Temporary cash investments |  |  | 44.1 |
Total | 29.7 |  | 81.6 |
Entergy Texas [Member] | Fair Value Inputs Level 1 [Member] | Securitization Recovery Trust Account [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Assets other than temporary cash investments | 29.7 |  | 37.5 |
Entergy Texas [Member] | Fair Value Inputs Level 1 [Member] | Fixed Transmission Rights (FTRs) [Member] | Fair Value, Measurements, Recurring [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Assets other than temporary cash investments | 7.4 |  | 18.4 |
Entergy Texas [Member] | Fair Value Inputs Level 3 [Member] | Securitization Recovery Trust Account [Member] | Fair Value, Measurements, Recurring [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Assets other than temporary cash investments | 7.4 |  | 18.4 |
Entergy Texas [Member] | Fair Value Inputs Level 3 [Member] | Fixed Transmission Rights (FTRs) [Member] | Fair Value, Measurements, Recurring [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Assets other than temporary cash investments | 7.4 |  | 18.4 |
System Energy [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Temporary cash investments | 83.1 |  | 64.6 |
Assets other than temporary cash investments | 619.3 |  | 603.9 |
Total | 702.4 |  | 668.5 |
System Energy [Member] | Equity Securities [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Assets other than temporary cash investments | 385.9 | [1] | 380.0 | [1]
System Energy [Member] | Debt Securities [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Assets other than temporary cash investments | 233.4 | [1] | 223.9 | [1]
System Energy [Member] | Fair Value Inputs Level 1 [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Temporary cash investments | 83.1 |  | 64.6 |
Total | 239.4 |  | 219.7 |
System Energy [Member] | Fair Value Inputs Level 1 [Member] | Equity Securities [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Assets other than temporary cash investments | 1.2 | [1] | 2.2 | [1]
System Energy [Member] | Fair Value Inputs Level 1 [Member] | Debt Securities [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Assets other than temporary cash investments | 155.1 | [1] | 152.9 | [1]
System Energy [Member] | Fair Value Inputs Level 2 [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Total | 463.0 |  | 448.8 |
System Energy [Member] | Fair Value Inputs Level 2 [Member] | Equity Securities [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Assets other than temporary cash investments | 384.7 | [1] | 377.8 | [1]
System Energy [Member] | Fair Value Inputs Level 2 [Member] | Debt Securities [Member] |  |  |  |
Assets at fair value on a recurring basis |  |  |  |
Assets other than temporary cash investments | $ 78.3 | [1] | $ 71.0 | [1]
[1] | The decommissioning trust funds hold equity and fixed income securities. Equity securities are invested to approximate the returns of major market indices. Fixed income securities are held in various governmental and corporate securities. See Note 9 to the financial statements herein for additional information on the investment portfolios.
[2] | Commingled equity funds may be redeemed bi-monthly.

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