Risk Management and Fair Values (Schedule of Derivatives Not Designated As Hedging Instruments) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024	Dec. 31, 2024
Financial transmission rights
Effect Of Derivative Instruments Not Designated As Hedging Instruments On The Consolidated Statements Of Income [Line Items]
Letters of Credit Outstanding, Amount	$ 4.0		$ 4.0		$ 2.0
Financial transmission rights | Not Designated as Hedging Instrument [Member]
Effect Of Derivative Instruments Not Designated As Hedging Instruments On The Consolidated Statements Of Income [Line Items]
Derivative, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	Utilities Operating Expense, Purchased Power	Utilities Operating Expense, Purchased Power	Utilities Operating Expense, Purchased Power	Utilities Operating Expense, Purchased Power
Derivative, Gain (Loss) on Derivative, Net	$ 36.0	$ 33.0	$ 150.0	$ 133.0
Derivative Asset, Subject to Master Netting Arrangement, before Offset	$ 31.0		$ 31.0
Derivative Asset, Statement of Financial Position [Extensible Enumeration]	Prepaid Expense and Other Assets, Current		Prepaid Expense and Other Assets, Current		Prepaid Expense and Other Assets, Current
Derivative Asset, Subject to Master Netting Arrangement, Liability Offset	$ (1.0)		$ (1.0)		$ (1.0)
Derivative Asset, Subject to Master Netting Arrangement, after Offset	$ 30.0		$ 30.0		$ 20.0
Derivative Liability, Statement of Financial Position [Extensible Enumeration]					Other Liabilities, Current
Derivative Liability, Subject to Master Netting Arrangement, after Offset					$ 1.0
Financial transmission rights | Not Designated as Hedging Instrument [Member] | Other Current Liabilities [Member]
Effect Of Derivative Instruments Not Designated As Hedging Instruments On The Consolidated Statements Of Income [Line Items]
Derivative Asset, Subject to Master Netting Arrangement, before Offset					0.0
Financial transmission rights | Not Designated as Hedging Instrument [Member] | Prepaid Expenses and Other Current Assets
Effect Of Derivative Instruments Not Designated As Hedging Instruments On The Consolidated Statements Of Income [Line Items]
Derivative Asset, Subject to Master Netting Arrangement, before Offset					21.0
Natural Gas Swaps | Not Designated as Hedging Instrument [Member]
Effect Of Derivative Instruments Not Designated As Hedging Instruments On The Consolidated Statements Of Income [Line Items]
Derivative, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	Utilities Operating Expense, Fuel Used	Utilities Operating Expense, Fuel Used	Utilities Operating Expense, Fuel Used	Utilities Operating Expense, Fuel Used
Derivative, Gain (Loss) on Derivative, Net	$ (6.0)	$ (1.0)	$ (7.0)	$ (7.0)
Derivative Asset, Subject to Master Netting Arrangement, before Offset					$ 2.0
Derivative Asset, Statement of Financial Position [Extensible Enumeration]					Prepaid Expense and Other Assets, Current
Derivative Asset, Subject to Master Netting Arrangement, Liability Offset					$ 0.0
Derivative Asset, Subject to Master Netting Arrangement, after Offset					2.0
Derivative Liability, Statement of Financial Position [Extensible Enumeration]	Other Liabilities, Current		Other Liabilities, Current
Derivative Liability, Subject to Master Netting Arrangement, Asset Offset	$ 0.0		$ 0.0
Derivative Liability, Subject to Master Netting Arrangement, after Offset	5.0		5.0
Derivative Liability, Subject to Master Netting Arrangement, before Offset	5.0		5.0
Entergy Arkansas [Member] | Uncommitted Credit Facility of $25 Million [Member]
Effect Of Derivative Instruments Not Designated As Hedging Instruments On The Consolidated Statements Of Income [Line Items]
Letters of Credit Outstanding, Amount	19.8		19.8
Entergy Arkansas [Member] | Financial Transmission Rights (FTRs) [Member] | Uncommitted Credit Facility of $25 Million [Member]
Effect Of Derivative Instruments Not Designated As Hedging Instruments On The Consolidated Statements Of Income [Line Items]
Letters of Credit Outstanding, Amount	2.1		2.1
Entergy Arkansas [Member] | Financial transmission rights
Effect Of Derivative Instruments Not Designated As Hedging Instruments On The Consolidated Statements Of Income [Line Items]
Letters of Credit Outstanding, Amount	$ 2.1		$ 2.1		0.5
Entergy Arkansas [Member] | Financial transmission rights | Not Designated as Hedging Instrument [Member]
Effect Of Derivative Instruments Not Designated As Hedging Instruments On The Consolidated Statements Of Income [Line Items]
Derivative, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	Utilities Operating Expense, Purchased Power	Utilities Operating Expense, Purchased Power	Utilities Operating Expense, Purchased Power	Utilities Operating Expense, Purchased Power
Derivative, Gain (Loss) on Derivative, Net	$ 9.7	$ 12.5	$ 37.9	$ 51.4
Derivative Asset, Subject to Master Netting Arrangement, before Offset	$ 8.0		$ 8.0		$ 8.6
Derivative Asset, Statement of Financial Position [Extensible Enumeration]	Prepaid Expense and Other Assets, Current		Prepaid Expense and Other Assets, Current		Prepaid Expense and Other Assets, Current
Derivative Asset, Subject to Master Netting Arrangement, Liability Offset	$ 0.0		$ 0.0		$ (0.1)
Derivative Asset, Subject to Master Netting Arrangement, after Offset	8.0		8.0		8.5
Entergy Louisiana [Member] | Uncommitted Credit Facility of $125 Million [Member]
Effect Of Derivative Instruments Not Designated As Hedging Instruments On The Consolidated Statements Of Income [Line Items]
Letters of Credit Outstanding, Amount	117.0		117.0
Entergy Louisiana [Member] | Financial Transmission Rights (FTRs) [Member] | Uncommitted Credit Facility of $125 Million [Member]
Effect Of Derivative Instruments Not Designated As Hedging Instruments On The Consolidated Statements Of Income [Line Items]
Letters of Credit Outstanding, Amount	0.5		0.5
Entergy Louisiana [Member] | Financial transmission rights
Effect Of Derivative Instruments Not Designated As Hedging Instruments On The Consolidated Statements Of Income [Line Items]
Letters of Credit Outstanding, Amount	$ 0.5		$ 0.5		0.1
Entergy Louisiana [Member] | Financial transmission rights | Not Designated as Hedging Instrument [Member]
Effect Of Derivative Instruments Not Designated As Hedging Instruments On The Consolidated Statements Of Income [Line Items]
Derivative, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	Utilities Operating Expense, Purchased Power	Utilities Operating Expense, Purchased Power	Utilities Operating Expense, Purchased Power	Utilities Operating Expense, Purchased Power
Derivative, Gain (Loss) on Derivative, Net	$ 16.0	$ 14.1	$ 80.0	$ 55.3
Derivative Asset, Subject to Master Netting Arrangement, before Offset	$ 18.6		$ 18.6		$ 8.7
Derivative Asset, Statement of Financial Position [Extensible Enumeration]	Prepaid Expense and Other Assets, Current		Prepaid Expense and Other Assets, Current		Prepaid Expense and Other Assets, Current
Derivative Asset, Subject to Master Netting Arrangement, Liability Offset	$ (0.2)		$ (0.2)		$ (0.1)
Derivative Asset, Subject to Master Netting Arrangement, after Offset	18.4		18.4		8.6
Entergy Mississippi [Member] | Financial transmission rights
Effect Of Derivative Instruments Not Designated As Hedging Instruments On The Consolidated Statements Of Income [Line Items]
Letters of Credit Outstanding, Amount	$ 1.2		$ 1.2		0.8
Entergy Mississippi [Member] | Financial transmission rights | Not Designated as Hedging Instrument [Member]
Effect Of Derivative Instruments Not Designated As Hedging Instruments On The Consolidated Statements Of Income [Line Items]
Derivative, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	Utilities Operating Expense, Purchased Power	Utilities Operating Expense, Purchased Power	Utilities Operating Expense, Purchased Power	Utilities Operating Expense, Purchased Power
Derivative, Gain (Loss) on Derivative, Net	$ 4.2	$ 2.0	$ 9.3	$ 5.1
Derivative Asset, Subject to Master Netting Arrangement, before Offset	$ 0.4		$ 0.4		0.4
Derivative Asset, Statement of Financial Position [Extensible Enumeration]	Prepaid Expense and Other Assets, Current		Prepaid Expense and Other Assets, Current
Derivative Asset, Subject to Master Netting Arrangement, Liability Offset	$ 0.0		$ 0.0		$ (0.9)
Derivative Asset, Subject to Master Netting Arrangement, after Offset	$ 0.4		$ 0.4
Derivative Liability, Statement of Financial Position [Extensible Enumeration]					Other Liabilities, Current
Derivative Liability, Subject to Master Netting Arrangement, after Offset					$ 0.5
Entergy Mississippi [Member] | Natural Gas Swaps | Not Designated as Hedging Instrument [Member]
Effect Of Derivative Instruments Not Designated As Hedging Instruments On The Consolidated Statements Of Income [Line Items]
Derivative, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	Utilities Operating Expense, Fuel Used	Utilities Operating Expense, Fuel Used	Utilities Operating Expense, Fuel Used	Utilities Operating Expense, Fuel Used
Derivative, Gain (Loss) on Derivative, Net	$ (6.2)	$ 0.9	$ (7.4)	$ 6.2
Derivative Asset, Subject to Master Netting Arrangement, before Offset					$ 1.6
Derivative Asset, Statement of Financial Position [Extensible Enumeration]					Prepaid Expense and Other Assets, Current
Derivative Asset, Subject to Master Netting Arrangement, Liability Offset					$ 0.0
Derivative Asset, Subject to Master Netting Arrangement, after Offset					1.6
Derivative Liability, Statement of Financial Position [Extensible Enumeration]	Other Liabilities, Current		Other Liabilities, Current
Derivative Liability, Subject to Master Netting Arrangement, Asset Offset	$ 0.0		$ 0.0
Derivative Liability, Subject to Master Netting Arrangement, after Offset	4.9		4.9
Derivative Liability, Subject to Master Netting Arrangement, before Offset	$ (4.9)		$ (4.9)
Entergy New Orleans [Member] | Financial transmission rights
Effect Of Derivative Instruments Not Designated As Hedging Instruments On The Consolidated Statements Of Income [Line Items]
Letters of Credit Outstanding, Amount					0.1
Entergy New Orleans [Member] | Financial transmission rights | Not Designated as Hedging Instrument [Member]
Effect Of Derivative Instruments Not Designated As Hedging Instruments On The Consolidated Statements Of Income [Line Items]
Derivative, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	Utilities Operating Expense, Purchased Power	Utilities Operating Expense, Purchased Power	Utilities Operating Expense, Purchased Power	Utilities Operating Expense, Purchased Power
Derivative, Gain (Loss) on Derivative, Net	$ 1.7	$ 1.2	$ 12.8	$ 5.6
Derivative Asset, Subject to Master Netting Arrangement, before Offset	$ 2.2		$ 2.2		$ 1.3
Derivative Asset, Statement of Financial Position [Extensible Enumeration]	Prepaid Expense and Other Assets, Current		Prepaid Expense and Other Assets, Current		Prepaid Expense and Other Assets, Current
Derivative Asset, Subject to Master Netting Arrangement, Liability Offset	$ 0.0		$ 0.0		$ 0.0
Derivative Asset, Subject to Master Netting Arrangement, after Offset	$ 2.2		$ 2.2		1.3
Entergy New Orleans [Member] | Natural Gas Swaps | Not Designated as Hedging Instrument [Member]
Effect Of Derivative Instruments Not Designated As Hedging Instruments On The Consolidated Statements Of Income [Line Items]
Derivative, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]				Utilities Operating Expense, Fuel Used
Derivative, Gain (Loss) on Derivative, Net				$ 0.5
Entergy Texas [Member] | Financial transmission rights
Effect Of Derivative Instruments Not Designated As Hedging Instruments On The Consolidated Statements Of Income [Line Items]
Letters of Credit Outstanding, Amount					0.3
Entergy Texas [Member] | Financial transmission rights | Not Designated as Hedging Instrument [Member]
Effect Of Derivative Instruments Not Designated As Hedging Instruments On The Consolidated Statements Of Income [Line Items]
Derivative, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	Utilities Operating Expense, Purchased Power	Utilities Operating Expense, Purchased Power	Utilities Operating Expense, Purchased Power	Utilities Operating Expense, Purchased Power
Derivative, Gain (Loss) on Derivative, Net	$ 3.9	$ 3.4	$ 9.8	$ 15.5
Derivative Asset, Subject to Master Netting Arrangement, before Offset	$ 2.0		$ 2.0		$ 2.0
Derivative Asset, Statement of Financial Position [Extensible Enumeration]	Prepaid Expense and Other Assets, Current		Prepaid Expense and Other Assets, Current		Prepaid Expense and Other Assets, Current
Derivative Asset, Subject to Master Netting Arrangement, Liability Offset	$ (0.6)		$ (0.6)		$ (0.1)
Derivative Asset, Subject to Master Netting Arrangement, after Offset	$ 1.4		$ 1.4		$ 1.9