Risk Management and Fair Values (Assets And Liabilities At Fair Value On A Recurring Basis) (Details) - USD ($) $ in Millions		Jun. 30, 2016	Dec. 31, 2015
Assets at fair value on a recurring basis
Assets other than temporary cash investments		$ 5,556.0	$ 5,350.0
Fair Value, Measurements, Recurring [Member]
Assets at fair value on a recurring basis
Temporary cash investments		893.0	1,287.0
Liabilities at fair value on a recurring basis
Total			15.0
Assets, Fair Value Disclosure		7,058.0	7,330.0
Gas Hedge Contracts [Member] | Fair Value, Measurements, Recurring [Member]
Liabilities at fair value on a recurring basis
Liabilities, Fair Value Disclosure on Recurring Basis			9.0
Power Contracts Liabilities [Member] | Fair Value, Measurements, Recurring [Member]
Liabilities at fair value on a recurring basis
Liabilities, Fair Value Disclosure on Recurring Basis		11.0	6.0
Equity Securities [Member] | Fair Value, Measurements, Recurring [Member]
Assets at fair value on a recurring basis
Assets other than temporary cash investments	[1]	464.0	468.0
Debt Securities [Member] | Fair Value, Measurements, Recurring [Member]
Assets at fair value on a recurring basis
Assets other than temporary cash investments	[1]	2,273.0	2,155.0
Common trust funds valued using Net Asset Value [Domain] | Fair Value, Measurements, Recurring [Member]
Assets at fair value on a recurring basis
Assets other than temporary cash investments	[1],[2]	2,819.0	2,727.0
Power Contracts Assets [Member] | Fair Value, Measurements, Recurring [Member]
Assets at fair value on a recurring basis
Assets other than temporary cash investments		77.0	195.0
Storm Reserve Escrow Account [Member] | Fair Value, Measurements, Recurring [Member]
Assets at fair value on a recurring basis
Assets other than temporary cash investments		433.0	425.0
Gas Hedge Contracts Assets [Member] | Fair Value, Measurements, Recurring [Member]
Assets at fair value on a recurring basis
Assets other than temporary cash investments		16.0
Securitization Recovery Trust Account [Member] | Fair Value, Measurements, Recurring [Member]
Assets at fair value on a recurring basis
Assets other than temporary cash investments		37.0	50.0
Fixed Transmission Rights (FTRs) [Member] | Fair Value, Measurements, Recurring [Member]
Assets at fair value on a recurring basis
Assets other than temporary cash investments		46.0	23.0
Fair Value Inputs Level 1 [Member]
Assets at fair value on a recurring basis
Temporary cash investments		893.0	1,287.0
Liabilities at fair value on a recurring basis
Total			9.0
Assets, Fair Value Disclosure		2,896.0	3,291.0
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			9.0
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		0.0	0.0
Fair Value Inputs Level 1 [Member] | Equity Securities [Member]
Assets at fair value on a recurring basis
Assets other than temporary cash investments	[1]	464.0	468.0
Fair Value Inputs Level 1 [Member] | Debt Securities [Member]
Assets at fair value on a recurring basis
Assets other than temporary cash investments	[1]	1,053.0	1,061.0
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	0.0
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		433.0	425.0
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		16.0
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		37.0	50.0
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	0.0
Fair Value, Inputs, Level 2 [Member]
Assets at fair value on a recurring basis
Temporary cash investments		0.0	0.0
Liabilities at fair value on a recurring basis
Total			0.0
Assets, Fair Value Disclosure		1,220.0	1,094.0
Fair Value, Inputs, Level 2 [Member] | Gas Hedge Contracts [Member]
Liabilities at fair value on a recurring basis
Liabilities, Fair Value Disclosure on Recurring Basis			0.0
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		0.0	0.0
Fair Value, Inputs, Level 2 [Member] | Equity Securities [Member]
Assets at fair value on a recurring basis
Assets other than temporary cash investments	[1]	0.0	0.0
Fair Value, Inputs, Level 2 [Member] | Debt Securities [Member]
Assets at fair value on a recurring basis
Assets other than temporary cash investments	[1]	1,220.0	1,094.0
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	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	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		0.0
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	0.0
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	0.0
Fair Value, Inputs, Level 3 [Member]
Assets at fair value on a recurring basis
Temporary cash investments		0.0	0.0
Liabilities at fair value on a recurring basis
Total			6.0
Assets, Fair Value Disclosure		123.0	218.0
Fair Value, Inputs, Level 3 [Member] | Gas Hedge Contracts [Member]
Liabilities at fair value on a recurring basis
Liabilities, Fair Value Disclosure on Recurring Basis			0.0
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		11.0	6.0
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	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	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		77.0	195.0
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	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		0.0
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	0.0
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		46.0	23.0
Entergy Louisiana [Member]
Assets at fair value on a recurring basis
Assets other than temporary cash investments		1,094.8	1,042.3
Entergy Louisiana [Member] | Fair Value, Measurements, Recurring [Member]
Assets at fair value on a recurring basis
Temporary cash investments		50.1	34.8
Liabilities at fair value on a recurring basis
Assets, Fair Value Disclosure		1,482.1	1,379.2
Entergy Louisiana [Member] | Gas Hedge Contracts [Member] | Fair Value, Measurements, Recurring [Member]
Liabilities at fair value on a recurring basis
Liabilities, Fair Value Disclosure on Recurring Basis			7.0
Entergy Louisiana [Member] | Equity Securities [Member] | Fair Value, Measurements, Recurring [Member]
Assets at fair value on a recurring basis
Assets other than temporary cash investments	[3]	6.9	7.1
Entergy Louisiana [Member] | Debt Securities [Member] | Fair Value, Measurements, Recurring [Member]
Assets at fair value on a recurring basis
Assets other than temporary cash investments	[3]	436.2	409.9
Entergy Louisiana [Member] | Common trust funds valued using Net Asset Value [Domain] | Fair Value, Measurements, Recurring [Member]
Assets at fair value on a recurring basis
Assets other than temporary cash investments	[1]	651.7	625.3
Entergy Louisiana [Member] | Storm Reserve Escrow Account [Member] | Fair Value, Measurements, Recurring [Member]
Assets at fair value on a recurring basis
Assets other than temporary cash investments		305.2	290.4
Entergy 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		12.8
Entergy Louisiana [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		3.0	3.2
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		16.2	8.5
Entergy Louisiana [Member] | Fair Value Inputs Level 1 [Member] | Fair Value, Measurements, Recurring [Member]
Assets at fair value on a recurring basis
Temporary cash investments		50.1	34.8
Liabilities at fair value on a recurring basis
Assets, Fair Value Disclosure		515.0	496.6
Entergy Louisiana [Member] | Fair Value Inputs Level 1 [Member] | Gas Hedge Contracts [Member] | Fair Value, Measurements, Recurring [Member]
Liabilities at fair value on a recurring basis
Liabilities, Fair Value Disclosure on Recurring Basis			7.0
Entergy Louisiana [Member] | Fair Value Inputs Level 1 [Member] | Equity Securities [Member] | Fair Value, Measurements, Recurring [Member]
Assets at fair value on a recurring basis
Assets other than temporary cash investments	[3]	6.9	7.1
Entergy Louisiana [Member] | Fair Value Inputs Level 1 [Member] | Debt Securities [Member] | Fair Value, Measurements, Recurring [Member]
Assets at fair value on a recurring basis
Assets other than temporary cash investments	[3]	137.0	161.1
Entergy Louisiana [Member] | Fair Value Inputs Level 1 [Member] | Storm Reserve Escrow Account [Member] | Fair Value, Measurements, Recurring [Member]
Assets at fair value on a recurring basis
Assets other than temporary cash investments		305.2	290.4
Entergy 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		12.8
Entergy Louisiana [Member] | Fair Value Inputs Level 1 [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		3.0	3.2
Entergy Louisiana [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		0.0	0.0
Entergy Louisiana [Member] | Fair Value, Inputs, Level 2 [Member] | Fair Value, Measurements, Recurring [Member]
Assets at fair value on a recurring basis
Temporary cash investments		0.0	0.0
Liabilities at fair value on a recurring basis
Assets, Fair Value Disclosure		299.2	248.8
Entergy Louisiana [Member] | Fair Value, Inputs, Level 2 [Member] | Gas Hedge Contracts [Member] | Fair Value, Measurements, Recurring [Member]
Liabilities at fair value on a recurring basis
Liabilities, Fair Value Disclosure on Recurring Basis			0.0
Entergy Louisiana [Member] | Fair Value, Inputs, Level 2 [Member] | Equity Securities [Member] | Fair Value, Measurements, Recurring [Member]
Assets at fair value on a recurring basis
Assets other than temporary cash investments	[3]	0.0	0.0
Entergy Louisiana [Member] | Fair Value, Inputs, Level 2 [Member] | Debt Securities [Member] | Fair Value, Measurements, Recurring [Member]
Assets at fair value on a recurring basis
Assets other than temporary cash investments	[3]	299.2	248.8
Entergy Louisiana [Member] | Fair Value, Inputs, Level 2 [Member] | Storm Reserve Escrow Account [Member] | Fair Value, Measurements, Recurring [Member]
Assets at fair value on a recurring basis
Assets other than temporary cash investments		0.0	0.0
Entergy Louisiana [Member] | 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		0.0
Entergy Louisiana [Member] | Fair Value, Inputs, Level 2 [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		0.0	0.0
Entergy Louisiana [Member] | 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	0.0
Entergy Louisiana [Member] | Fair Value, Inputs, Level 3 [Member] | Fair Value, Measurements, Recurring [Member]
Assets at fair value on a recurring basis
Temporary cash investments		0.0	0.0
Liabilities at fair value on a recurring basis
Assets, Fair Value Disclosure		16.2	8.5
Entergy Louisiana [Member] | Fair Value, Inputs, Level 3 [Member] | Gas Hedge Contracts [Member] | Fair Value, Measurements, Recurring [Member]
Liabilities at fair value on a recurring basis
Liabilities, Fair Value Disclosure on Recurring Basis			0.0
Entergy Louisiana [Member] | Fair Value, Inputs, Level 3 [Member] | Equity Securities [Member] | Fair Value, Measurements, Recurring [Member]
Assets at fair value on a recurring basis
Assets other than temporary cash investments	[3]	0.0	0.0
Entergy Louisiana [Member] | Fair Value, Inputs, Level 3 [Member] | Debt Securities [Member] | Fair Value, Measurements, Recurring [Member]
Assets at fair value on a recurring basis
Assets other than temporary cash investments	[3]	0.0	0.0
Entergy Louisiana [Member] | Fair Value, Inputs, Level 3 [Member] | Storm Reserve Escrow Account [Member] | Fair Value, Measurements, Recurring [Member]
Assets at fair value on a recurring basis
Assets other than temporary cash investments		0.0	0.0
Entergy Louisiana [Member] | 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		0.0
Entergy Louisiana [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		0.0	0.0
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		16.2	8.5
Entergy Arkansas [Member]
Assets at fair value on a recurring basis
Assets other than temporary cash investments		802.8	771.3
Entergy Arkansas [Member] | Fair Value, Measurements, Recurring [Member]
Assets at fair value on a recurring basis
Temporary cash investments		11.3
Liabilities at fair value on a recurring basis
Assets, Fair Value Disclosure		838.4	795.6
Entergy Arkansas [Member] | Equity Securities [Member] | Fair Value, Measurements, Recurring [Member]
Assets at fair value on a recurring basis
Assets other than temporary cash investments	[3]	16.8	3.0
Entergy Arkansas [Member] | Debt Securities [Member] | Fair Value, Measurements, Recurring [Member]
Assets at fair value on a recurring basis
Assets other than temporary cash investments	[3]	305.2	303.9
Entergy Arkansas [Member] | Common trust funds valued using Net Asset Value [Domain] | Fair Value, Measurements, Recurring [Member]
Assets at fair value on a recurring basis
Assets other than temporary cash investments	[1]	480.8	464.4
Entergy Arkansas [Member] | Storm Reserve Escrow Account [Member] | Fair Value, Measurements, Recurring [Member]
Assets at fair value on a recurring basis
Assets other than temporary cash investments		7.1	12.2
Entergy Arkansas [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		3.2	4.2
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		14.0	7.9
Entergy Arkansas [Member] | Fair Value Inputs Level 1 [Member] | Fair Value, Measurements, Recurring [Member]
Assets at fair value on a recurring basis
Temporary cash investments		11.3
Liabilities at fair value on a recurring basis
Assets, Fair Value Disclosure		135.8	129.9
Entergy Arkansas [Member] | Fair Value Inputs Level 1 [Member] | Equity Securities [Member] | Fair Value, Measurements, Recurring [Member]
Assets at fair value on a recurring basis
Assets other than temporary cash investments	[3]	16.8	3.0
Entergy Arkansas [Member] | Fair Value Inputs Level 1 [Member] | Debt Securities [Member] | Fair Value, Measurements, Recurring [Member]
Assets at fair value on a recurring basis
Assets other than temporary cash investments	[3]	97.4	110.5
Entergy Arkansas [Member] | Fair Value Inputs Level 1 [Member] | Storm Reserve Escrow Account [Member] | Fair Value, Measurements, Recurring [Member]
Assets at fair value on a recurring basis
Assets other than temporary cash investments		7.1	12.2
Entergy Arkansas [Member] | Fair Value Inputs Level 1 [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		3.2	4.2
Entergy Arkansas [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		0.0	0.0
Entergy Arkansas [Member] | Fair Value, Inputs, Level 2 [Member] | Fair Value, Measurements, Recurring [Member]
Assets at fair value on a recurring basis
Temporary cash investments		0.0
Liabilities at fair value on a recurring basis
Assets, Fair Value Disclosure		207.8	193.4
Entergy Arkansas [Member] | Fair Value, Inputs, Level 2 [Member] | Equity Securities [Member] | Fair Value, Measurements, Recurring [Member]
Assets at fair value on a recurring basis
Assets other than temporary cash investments	[3]	0.0	0.0
Entergy Arkansas [Member] | Fair Value, Inputs, Level 2 [Member] | Debt Securities [Member] | Fair Value, Measurements, Recurring [Member]
Assets at fair value on a recurring basis
Assets other than temporary cash investments	[3]	207.8	193.4
Entergy Arkansas [Member] | Fair Value, Inputs, Level 2 [Member] | Storm Reserve Escrow Account [Member] | Fair Value, Measurements, Recurring [Member]
Assets at fair value on a recurring basis
Assets other than temporary cash investments		0.0	0.0
Entergy Arkansas [Member] | Fair Value, Inputs, Level 2 [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		0.0	0.0
Entergy Arkansas [Member] | 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	0.0
Entergy Arkansas [Member] | Fair Value, Inputs, Level 3 [Member] | Fair Value, Measurements, Recurring [Member]
Assets at fair value on a recurring basis
Temporary cash investments		0.0
Liabilities at fair value on a recurring basis
Assets, Fair Value Disclosure		14.0	7.9
Entergy Arkansas [Member] | Fair Value, Inputs, Level 3 [Member] | Equity Securities [Member] | Fair Value, Measurements, Recurring [Member]
Assets at fair value on a recurring basis
Assets other than temporary cash investments	[3]	0.0	0.0
Entergy Arkansas [Member] | Fair Value, Inputs, Level 3 [Member] | Debt Securities [Member] | Fair Value, Measurements, Recurring [Member]
Assets at fair value on a recurring basis
Assets other than temporary cash investments	[3]	0.0	0.0
Entergy Arkansas [Member] | Fair Value, Inputs, Level 3 [Member] | Storm Reserve Escrow Account [Member] | Fair Value, Measurements, Recurring [Member]
Assets at fair value on a recurring basis
Assets other than temporary cash investments		0.0	0.0
Entergy Arkansas [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		0.0	0.0
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		14.0	7.9
Entergy Mississippi [Member] | Fair Value, Measurements, Recurring [Member]
Assets at fair value on a recurring basis
Temporary cash investments		105.3	144.2
Liabilities at fair value on a recurring basis
Assets, Fair Value Disclosure		145.4	188.3
Entergy Mississippi [Member] | Gas Hedge Contracts [Member] | Fair Value, Measurements, Recurring [Member]
Liabilities at fair value on a recurring basis
Liabilities, Fair Value Disclosure on Recurring Basis			1.3
Entergy Mississippi [Member] | Storm Reserve Escrow Account [Member] | Fair Value, Measurements, Recurring [Member]
Assets at fair value on a recurring basis
Assets other than temporary cash investments		31.8	41.7
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		2.7
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		5.6	2.4
Entergy Mississippi [Member] | Fair Value Inputs Level 1 [Member] | Fair Value, Measurements, Recurring [Member]
Assets at fair value on a recurring basis
Temporary cash investments		105.3	144.2
Liabilities at fair value on a recurring basis
Assets, Fair Value Disclosure		139.8	185.9
Entergy Mississippi [Member] | Fair Value Inputs Level 1 [Member] | Gas Hedge Contracts [Member] | Fair Value, Measurements, Recurring [Member]
Liabilities at fair value on a recurring basis
Liabilities, Fair Value Disclosure on Recurring Basis			1.3
Entergy Mississippi [Member] | Fair Value Inputs Level 1 [Member] | Storm Reserve Escrow Account [Member] | Fair Value, Measurements, Recurring [Member]
Assets at fair value on a recurring basis
Assets other than temporary cash investments		31.8	41.7
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		2.7
Entergy Mississippi [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		0.0	0.0
Entergy Mississippi [Member] | Fair Value, Inputs, Level 2 [Member] | Fair Value, Measurements, Recurring [Member]
Assets at fair value on a recurring basis
Temporary cash investments		0.0	0.0
Liabilities at fair value on a recurring basis
Assets, Fair Value Disclosure		0.0	0.0
Entergy Mississippi [Member] | Fair Value, Inputs, Level 2 [Member] | Gas Hedge Contracts [Member] | Fair Value, Measurements, Recurring [Member]
Liabilities at fair value on a recurring basis
Liabilities, Fair Value Disclosure on Recurring Basis			0.0
Entergy Mississippi [Member] | Fair Value, Inputs, Level 2 [Member] | Storm Reserve Escrow Account [Member] | Fair Value, Measurements, Recurring [Member]
Assets at fair value on a recurring basis
Assets other than temporary cash investments		0.0	0.0
Entergy Mississippi [Member] | 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		0.0
Entergy Mississippi [Member] | 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	0.0
Entergy Mississippi [Member] | Fair Value, Inputs, Level 3 [Member] | Fair Value, Measurements, Recurring [Member]
Assets at fair value on a recurring basis
Temporary cash investments		0.0	0.0
Liabilities at fair value on a recurring basis
Assets, Fair Value Disclosure		5.6	2.4
Entergy Mississippi [Member] | Fair Value, Inputs, Level 3 [Member] | Gas Hedge Contracts [Member] | Fair Value, Measurements, Recurring [Member]
Liabilities at fair value on a recurring basis
Liabilities, Fair Value Disclosure on Recurring Basis			0.0
Entergy Mississippi [Member] | Fair Value, Inputs, Level 3 [Member] | Storm Reserve Escrow Account [Member] | Fair Value, Measurements, Recurring [Member]
Assets at fair value on a recurring basis
Assets other than temporary cash investments		0.0	0.0
Entergy Mississippi [Member] | 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		0.0
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		5.6	2.4
Entergy New Orleans [Member] | Fair Value, Measurements, Recurring [Member]
Assets at fair value on a recurring basis
Temporary cash investments		23.4	87.8
Liabilities at fair value on a recurring basis
Assets, Fair Value Disclosure		115.0	174.9
Entergy New Orleans [Member] | Gas Hedge Contracts [Member] | Fair Value, Measurements, Recurring [Member]
Liabilities at fair value on a recurring basis
Liabilities, Fair Value Disclosure on Recurring Basis			0.5
Entergy New Orleans [Member] | Storm Reserve Escrow Account [Member] | Fair Value, Measurements, Recurring [Member]
Assets at fair value on a recurring basis
Assets other than temporary cash investments		88.3	81.0
Entergy New Orleans [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		1.3	4.6
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		2.0	1.5
Entergy New Orleans [Member] | Fair Value Inputs Level 1 [Member] | Fair Value, Measurements, Recurring [Member]
Assets at fair value on a recurring basis
Temporary cash investments		23.4	87.8
Liabilities at fair value on a recurring basis
Assets, Fair Value Disclosure		113.0	173.4
Entergy New Orleans [Member] | Fair Value Inputs Level 1 [Member] | Gas Hedge Contracts [Member] | Fair Value, Measurements, Recurring [Member]
Liabilities at fair value on a recurring basis
Liabilities, Fair Value Disclosure on Recurring Basis			0.5
Entergy New Orleans [Member] | Fair Value Inputs Level 1 [Member] | Storm Reserve Escrow Account [Member] | Fair Value, Measurements, Recurring [Member]
Assets at fair value on a recurring basis
Assets other than temporary cash investments		88.3	81.0
Entergy New Orleans [Member] | Fair Value Inputs Level 1 [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		1.3	4.6
Entergy New Orleans [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		0.0	0.0
Entergy New Orleans [Member] | Fair Value, Inputs, Level 2 [Member] | Fair Value, Measurements, Recurring [Member]
Assets at fair value on a recurring basis
Temporary cash investments		0.0	0.0
Liabilities at fair value on a recurring basis
Assets, Fair Value Disclosure		0.0	0.0
Entergy New Orleans [Member] | Fair Value, Inputs, Level 2 [Member] | Gas Hedge Contracts [Member] | Fair Value, Measurements, Recurring [Member]
Liabilities at fair value on a recurring basis
Liabilities, Fair Value Disclosure on Recurring Basis			0.0
Entergy New Orleans [Member] | Fair Value, Inputs, Level 2 [Member] | Storm Reserve Escrow Account [Member] | Fair Value, Measurements, Recurring [Member]
Assets at fair value on a recurring basis
Assets other than temporary cash investments		0.0	0.0
Entergy New Orleans [Member] | Fair Value, Inputs, Level 2 [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		0.0	0.0
Entergy New Orleans [Member] | 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	0.0
Entergy New Orleans [Member] | Fair Value, Inputs, Level 3 [Member] | Fair Value, Measurements, Recurring [Member]
Assets at fair value on a recurring basis
Temporary cash investments		0.0	0.0
Liabilities at fair value on a recurring basis
Assets, Fair Value Disclosure		2.0	1.5
Entergy New Orleans [Member] | Fair Value, Inputs, Level 3 [Member] | Gas Hedge Contracts [Member] | Fair Value, Measurements, Recurring [Member]
Liabilities at fair value on a recurring basis
Liabilities, Fair Value Disclosure on Recurring Basis			0.0
Entergy New Orleans [Member] | Fair Value, Inputs, Level 3 [Member] | Storm Reserve Escrow Account [Member] | Fair Value, Measurements, Recurring [Member]
Assets at fair value on a recurring basis
Assets other than temporary cash investments		0.0	0.0
Entergy New Orleans [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		0.0	0.0
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		2.0	1.5
Entergy Texas [Member] | Fair Value, Measurements, Recurring [Member]
Assets at fair value on a recurring basis
Temporary cash investments		54.6
Liabilities at fair value on a recurring basis
Assets, Fair Value Disclosure		92.0	40.4
Entergy Texas [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		29.4	38.2
Entergy Texas [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		8.0	2.2
Entergy Texas [Member] | Fair Value Inputs Level 1 [Member] | Fair Value, Measurements, Recurring [Member]
Assets at fair value on a recurring basis
Temporary cash investments		54.6
Liabilities at fair value on a recurring basis
Assets, Fair Value Disclosure		84.0	38.2
Entergy Texas [Member] | Fair Value Inputs Level 1 [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		29.4	38.2
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		0.0	0.0
Entergy Texas [Member] | Fair Value, Inputs, Level 2 [Member] | Fair Value, Measurements, Recurring [Member]
Assets at fair value on a recurring basis
Temporary cash investments		0.0
Liabilities at fair value on a recurring basis
Assets, Fair Value Disclosure		0.0	0.0
Entergy Texas [Member] | Fair Value, Inputs, Level 2 [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		0.0	0.0
Entergy Texas [Member] | 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	0.0
Entergy Texas [Member] | Fair Value, Inputs, Level 3 [Member] | Fair Value, Measurements, Recurring [Member]
Assets at fair value on a recurring basis
Temporary cash investments		0.0
Liabilities at fair value on a recurring basis
Assets, Fair Value Disclosure		8.0	2.2
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		0.0	0.0
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		8.0	2.2
System Energy [Member]
Assets at fair value on a recurring basis
Assets other than temporary cash investments		741.1	701.5
System Energy [Member] | Fair Value, Measurements, Recurring [Member]
Assets at fair value on a recurring basis
Temporary cash investments		138.0	222.0
Liabilities at fair value on a recurring basis
Assets, Fair Value Disclosure		879.1	923.5
System Energy [Member] | Equity Securities [Member] | Fair Value, Measurements, Recurring [Member]
Assets at fair value on a recurring basis
Assets other than temporary cash investments	[1]	0.7	1.8
System Energy [Member] | Debt Securities [Member] | Fair Value, Measurements, Recurring [Member]
Assets at fair value on a recurring basis
Assets other than temporary cash investments	[1]	303.7	277.8
System Energy [Member] | Common trust funds valued using Net Asset Value [Domain] | Fair Value, Measurements, Recurring [Member]
Assets at fair value on a recurring basis
Assets other than temporary cash investments	[1]	436.7	421.9
System Energy [Member] | Fair Value Inputs Level 1 [Member] | Fair Value, Measurements, Recurring [Member]
Assets at fair value on a recurring basis
Temporary cash investments		138.0	222.0
Liabilities at fair value on a recurring basis
Assets, Fair Value Disclosure		386.1	442.4
System Energy [Member] | Fair Value Inputs Level 1 [Member] | Equity Securities [Member] | Fair Value, Measurements, Recurring [Member]
Assets at fair value on a recurring basis
Assets other than temporary cash investments	[1]	0.7	1.8
System Energy [Member] | Fair Value Inputs Level 1 [Member] | Debt Securities [Member] | Fair Value, Measurements, Recurring [Member]
Assets at fair value on a recurring basis
Assets other than temporary cash investments	[1]	247.4	218.6
System Energy [Member] | Fair Value, Inputs, Level 2 [Member] | Fair Value, Measurements, Recurring [Member]
Assets at fair value on a recurring basis
Temporary cash investments		0.0	0.0
Liabilities at fair value on a recurring basis
Assets, Fair Value Disclosure		56.3	59.2
System Energy [Member] | Fair Value, Inputs, Level 2 [Member] | Equity Securities [Member] | Fair Value, Measurements, Recurring [Member]
Assets at fair value on a recurring basis
Assets other than temporary cash investments	[1]	0.0	0.0
System Energy [Member] | Fair Value, Inputs, Level 2 [Member] | Debt Securities [Member] | Fair Value, Measurements, Recurring [Member]
Assets at fair value on a recurring basis
Assets other than temporary cash investments	[1]	56.3	59.2
System Energy [Member] | Fair Value, Inputs, Level 3 [Member] | Fair Value, Measurements, Recurring [Member]
Assets at fair value on a recurring basis
Temporary cash investments		0.0	0.0
Liabilities at fair value on a recurring basis
Assets, Fair Value Disclosure		0.0	0.0
System Energy [Member] | Fair Value, Inputs, Level 3 [Member] | Equity Securities [Member] | Fair Value, Measurements, Recurring [Member]
Assets at fair value on a recurring basis
Assets other than temporary cash investments	[1]	0.0	0.0
System Energy [Member] | Fair Value, Inputs, Level 3 [Member] | Debt Securities [Member] | Fair Value, Measurements, Recurring [Member]
Assets at fair value on a recurring basis
Assets other than temporary cash investments	[1]	$ 0.0	$ 0.0

[1] (a)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] (b)Common trust funds are not publicly quoted, and are valued by the fund administrators using net asset value as a practical expedient. Accordingly, these funds are not assigned a level in the fair value table. The fund administrator of these investments allows daily trading at the net asset value and trades settle at a later date.The following table sets forth a reconciliation of changes in the net assets (liabilities) for the fair value of derivatives classified as Level 3 in the fair value hierarchy for the three months ended June 30, 2016 and 2015: 2016 2015 Power Contracts FTRs Power Contracts FTRs (In Millions)Balance as of April 1,$183 $9 $145 $15Total gains (losses) for the period (a) Included in earnings(9) — 22 —Included in OCI(53) — 131 —Included as a regulatory liability/asset— 20 — 18Issuances of FTRs— 55 — 80Purchases— — 4 —Settlements(55) (38) (98) (46)Balance as of June 30,$66 $46 $204 $67

[3] (a)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.(b)Common trust funds are not publicly quoted, and are valued by the fund administrators using net asset value as a practical expedient. Accordingly, these funds are not assigned a level in the fair value table. The fund administrator of these investments allows daily trading at the net asset value and trades settle at a later date.