RISK MANAGEMENT AND FAIR VALUES (Entergy Corporation, Entergy Arkansas, Entergy Louisiana, Entergy Mississippi, Entergy New Orleans, Entergy Texas, and System Energy) (Schedule of Derivatives Instruments) (Details) - USD ($) $ in Millions	Sep. 30, 2026	Dec. 31, 2025
Financial transmission rights
Liabilities:
Letters of Credit	$ 5.0	$ 2.0
Financial transmission rights | ENTERGY ARKANSAS, LLC
Liabilities:
Letters of Credit	3.2	0.1
Financial transmission rights | ENTERGY LOUISIANA, LLC
Liabilities:
Letters of Credit		0.8
Financial transmission rights | ENTERGY MISSISSIPPI, LLC
Liabilities:
Letters of Credit		0.8
Financial transmission rights | ENTERGY NEW ORLEANS, LLC
Liabilities:
Letters of Credit	0.5
Financial transmission rights | ENTERGY TEXAS, INC.
Liabilities:
Letters of Credit	1.0	0.1
Financial transmission rights | Not Designated as Hedging Instrument
Assets:
Gross Fair Value	$ 51.0	$ 27.0
Derivative Asset, Statement of Financial Position [Extensible Enumeration]	Prepayments and other	Prepayments and other
Offsetting Position	$ (4.0)	$ 0.0
Net Fair Value	47.0	27.0
Financial transmission rights | Not Designated as Hedging Instrument | ENTERGY ARKANSAS, LLC
Assets:
Gross Fair Value	$ 19.4	$ 5.5
Derivative Asset, Statement of Financial Position [Extensible Enumeration]	Prepayments and other	Prepayments and other
Offsetting Position	$ 0.0	$ 0.0
Net Fair Value	19.4	5.5
Financial transmission rights | Not Designated as Hedging Instrument | ENTERGY LOUISIANA, LLC
Assets:
Gross Fair Value	$ 24.8	$ 16.8
Derivative Asset, Statement of Financial Position [Extensible Enumeration]	Prepayments and other	Prepayments and other
Offsetting Position	$ 0.0	$ (0.1)
Net Fair Value	24.8	16.7
Financial transmission rights | Not Designated as Hedging Instrument | ENTERGY MISSISSIPPI, LLC
Assets:
Gross Fair Value	$ 0.2	$ 0.4
Derivative Asset, Statement of Financial Position [Extensible Enumeration]	Prepayments and other	Prepayments and other
Offsetting Position	$ (1.5)	$ 0.0
Net Fair Value	(1.3)	0.4
Financial transmission rights | Not Designated as Hedging Instrument | ENTERGY NEW ORLEANS, LLC
Assets:
Gross Fair Value	$ 3.4	$ 1.8
Derivative Asset, Statement of Financial Position [Extensible Enumeration]	Prepayments and other	Prepayments and other
Offsetting Position	$ 0.0	$ 0.0
Net Fair Value	3.4	1.8
Financial transmission rights | Not Designated as Hedging Instrument | ENTERGY TEXAS, INC.
Assets:
Gross Fair Value	$ 3.6	$ 2.3
Derivative Asset, Statement of Financial Position [Extensible Enumeration]	Prepayments and other	Prepayments and other
Offsetting Position	$ (2.8)	$ (0.2)
Net Fair Value	0.8	2.1
Interest rate swaps | Not Designated as Hedging Instrument
Assets:
Gross Fair Value		$ 1.0
Derivative Asset, Statement of Financial Position [Extensible Enumeration]		Prepayments and other
Offsetting Position		$ 0.0
Net Fair Value		1.0
Liabilities:
Gross Fair Value		$ 3.0
Derivative Liability, Statement of Financial Position [Extensible Enumeration]		Other
Offsetting Position		$ 0.0
Net Fair Value		3.0
Interest rate swaps | Not Designated as Hedging Instrument | ENTERGY TEXAS, INC.
Assets:
Gross Fair Value		$ 0.5
Derivative Asset, Statement of Financial Position [Extensible Enumeration]		Prepayments and other
Offsetting Position		$ 0.0
Net Fair Value		0.5
Interest rate swaps | Not Designated as Hedging Instrument | Location, Statement of Financial Position, Balance [Axis]: us-gaap:OtherAssetsNoncurrent
Assets:
Gross Fair Value	$ 7.0
Derivative Asset, Statement of Financial Position [Extensible Enumeration]	Other Assets, Noncurrent
Offsetting Position	$ 0.0
Net Fair Value	7.0
Interest rate swaps | Not Designated as Hedging Instrument | Location, Statement of Financial Position, Balance [Axis]: us-gaap:OtherAssetsNoncurrent | ENTERGY TEXAS, INC.
Assets:
Gross Fair Value	$ 7.3
Derivative Asset, Statement of Financial Position [Extensible Enumeration]	Other Assets, Noncurrent
Offsetting Position	$ 0.0
Net Fair Value	7.3
Interest rate swaps | Not Designated as Hedging Instrument | Location, Statement of Financial Position, Balance [Axis]: us-gaap:PrepaidExpenseAndOtherAssetsCurrent
Assets:
Gross Fair Value	$ 6.0
Derivative Asset, Statement of Financial Position [Extensible Enumeration]	Prepayments and other
Offsetting Position	$ 0.0
Net Fair Value	6.0
Interest rate swaps | Not Designated as Hedging Instrument | Location, Statement of Financial Position, Balance [Axis]: us-gaap:PrepaidExpenseAndOtherAssetsCurrent | ENTERGY TEXAS, INC.
Assets:
Gross Fair Value	$ 6.4
Derivative Asset, Statement of Financial Position [Extensible Enumeration]	Prepayments and other
Offsetting Position	$ 0.0
Net Fair Value	6.4
Natural gas swaps | Not Designated as Hedging Instrument
Liabilities:
Gross Fair Value	$ 4.0	$ 5.0
Derivative Liability, Statement of Financial Position [Extensible Enumeration]	Other Liabilities, Current	Other Liabilities, Current
Offsetting Position	$ 0.0	$ 0.0
Net Fair Value	4.0	5.0
Natural gas swaps | Not Designated as Hedging Instrument | ENTERGY LOUISIANA, LLC
Liabilities:
Gross Fair Value	$ 0.5
Derivative Liability, Statement of Financial Position [Extensible Enumeration]	Other Liabilities, Current
Offsetting Position	$ 0.0
Net Fair Value	0.5
Natural gas swaps | Not Designated as Hedging Instrument | ENTERGY MISSISSIPPI, LLC
Liabilities:
Gross Fair Value	$ 3.1	$ 5.3
Derivative Liability, Statement of Financial Position [Extensible Enumeration]	Other Liabilities, Current	Other Liabilities, Current
Offsetting Position	$ 0.0	$ 0.0
Net Fair Value	3.1	$ 5.3
Natural gas swaps | Not Designated as Hedging Instrument | Location, Statement of Financial Position, Balance [Axis]: us-gaap:OtherAssetsNoncurrent
Assets:
Gross Fair Value	$ 1.0
Derivative Asset, Statement of Financial Position [Extensible Enumeration]	Other Assets, Noncurrent
Offsetting Position	$ 0.0
Net Fair Value	1.0
Natural gas swaps | Not Designated as Hedging Instrument | Location, Statement of Financial Position, Balance [Axis]: us-gaap:OtherAssetsNoncurrent | ENTERGY LOUISIANA, LLC
Assets:
Gross Fair Value	$ 0.9
Derivative Asset, Statement of Financial Position [Extensible Enumeration]	Other Assets, Noncurrent
Offsetting Position	$ 0.0
Net Fair Value	$ 0.9