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Amount, after tax, of accumulated gain (loss) on derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness.

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Nominal or face amount used to calculate payment on derivative.

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The estimated net amount of unrealized gains or losses on interest rate cash flow hedges as of the balance sheet date expected to be reclassified to earnings within the next twelve months.

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Amount, after tax, of adjustments from accumulated other comprehensive income (AOCI) for gain (loss) from increase (decrease) in value of excluded component of derivative designated and qualifying as hedge. Adjustments include, but are not limited to, reclassifications for sale and settlement, and amounts recognized under systematic and rational method.

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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The cash inflow from a financial contract that meets the hedge criteria as either cash flow hedge, fair value hedge or hedge of net investment in foreign operations.

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Carrying amount as of the balance sheet date of capitalized costs of regulated entities that are expected to be recovered through revenue sources within one year or the normal operating cycle, if longer. Such costs are capitalized if they meet both of the following criteria: a. It is probable that future revenue in an amount at least equal to the capitalized cost will result from inclusion of that cost in allowable costs for rate-making purposes. b. Based on available evidence, the future revenue will be provided to permit recovery of the previously incurred cost rather than to provide for expected levels of similar future costs. If the revenue will be provided through an automatic rate-adjustment clause, this criterion requires that the regulator's intent clearly be to permit recovery of the previously incurred cost.

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Derivative Instruments and Hedging Activities (Details) MWh in Thousands	3 Months Ended				6 Months Ended		9 Months Ended
	Jun. 30, 2025 USD ($) MWh	Mar. 31, 2025 USD ($)	Jun. 30, 2024 USD ($)	Mar. 31, 2024 USD ($)	Jun. 30, 2025 USD ($) MWh	Jun. 30, 2024 USD ($)	Sep. 30, 2024 USD ($)	Dec. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)	Apr. 08, 2020 USD ($)
Other Comprehensive Income (Loss), Net of Tax	$ (434,000)	$ (434,000)	$ (434,000)	$ 7,386,000	$ (868,000)	$ 6,952,000
Interest Rate Cash Flow Hedge Gain (Loss) to be Reclassified During Next 12 Months, Net	1,737				1,737
Reclassification from AOCI, Current Period, Net of Tax, Attributable to Parent	(434,000)		(434,000)		(868,000)	326,000
Other Comprehensive Income (Loss), Derivative, Excluded Component, Increase (Decrease), Adjustments, after Tax	0		0		0	6,626,000
Regulatory assets	146,665,000				146,665,000			$ 134,328,000
AOCI, Cash Flow Hedge, Cumulative Gain (Loss), after Tax		34,944,000		$ 36,680,000				35,378,000	$ 29,294,000
Derivative, Amount of Hedged Item	$ 3				$ 3
Proceeds from Secured Lines of Credit							$ 300,000,000
2034 IPALCO Senior Notes
Accumulated Other Income (Loss)										$ 95,400,000
2030 IPALCO Senior Notes
Accumulated Other Income (Loss)										$ 72,300,000
FTR [Member] \| Not Designated as Hedging Instrument [Member]
Purchase of Units Derivative Instruments Financial Transmission Rights \| MWh	8,067				8,067
Sale of Units Derivative Instruments Financial Transmission Rights \| MWh	0				0
Derivative, Nonmonetary Notional Amount, Purchase (Sales), Net	$ 8,067,000				$ 8,067,000
Interest Rate Swap [Member]
Proceeds from Hedge, Financing Activities		$ 23,100,000
Derivative, Amount of Hedged Item	10				10
Interest Rate Swap [Member] \| Designated as Hedging Instrument [Member]
Derivative, Notional Amount	400,000,000				400,000,000
Interest Rate Contract [Member]
AOCI, Cash Flow Hedge, Cumulative Gain (Loss), after Tax	34,510,000		$ 36,246,000		34,510,000	$ 36,246,000
Other Current Assets [Member] \| FTR [Member] \| Not Designated as Hedging Instrument [Member]
Derivative Asset, Fair Value, Gross Asset								$ 1,526,000
Other Current Assets [Member] \| interest rate hedge \| Not Designated as Hedging Instrument [Member]
Derivative Asset, Fair Value, Gross Asset	$ 4,304,000				$ 4,304,000