Leases Leases (Present Value Of future Minimum Lease Payments Sale Leaseback Transactions) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended	12 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Long-term Debt, Fair Value	$ 18,628,268		$ 18,628,268		$ 15,880,239
Interest Expense, Debt	201,412	$ 195,311	603,517	$ 570,548
Entergy Arkansas [Member]
Long-term Debt, Fair Value	3,621,073		3,621,073		3,002,627
Interest Expense, Debt	35,454	31,632	104,664	92,315
Entergy Louisiana [Member]
Long-term Debt, Fair Value	8,038,675		8,038,675		6,834,134
Interest Expense, Debt	78,350	73,084	230,684	216,762
Entergy Mississippi [Member]
Long-term Debt, Fair Value	1,586,199		1,586,199		1,276,452
Interest Expense, Debt	15,922	13,950	45,804	41,916
Entergy New Orleans [Member]
Long-term Debt, Fair Value	522,688		522,688		491,569
Interest Expense, Debt	6,046	5,388	18,001	15,936
Entergy Texas [Member]
Long-term Debt, Fair Value	2,128,842		2,128,842		1,528,828
Interest Expense, Debt	21,379	21,760	63,992	65,646
System Energy [Member]
Long-term Debt, Fair Value	554,374		554,374		596,123
Interest Expense, Debt	$ 8,546	$ 9,753	$ 26,467	$ 28,734
Grand Gulf [Member] \| System Energy [Member]
Long-term Debt, Maturities, Repayments of Principal in Next Twelve Months					17,188
Long-term Debt, Maturities, Repayments of Principal in Year Two					17,188
Long-term Debt, Maturities, Repayments of Principal in Year Three					17,188
Long-term Debt, Maturities, Repayments of Principal in Year Four					17,188
Long-term Debt, Maturities, Repayments of Principal in Year Five					17,188
Long-term Debt, Maturities, Repayments of Principal after Year Five					223,437
Long-term Debt, Fair Value					309,377
Interest Expense, Debt					275,025
Long-term Debt					$ 34,352

Amount of the cost of borrowed funds accounted for as interest expense for debt.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Topic 470
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