Debt (Schedule Long-Term Indebtedness) (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Unamortized discount - net	$ (6,600)	$ (6,600)
Deferred financing costs	(25,400)	(26,000)
Long-term debt	2,651,793	2,651,185
Less: Current Portion of Long-term Debt	94,945	94,907
Net Consolidated IPALCO Long-term Debt	2,556,848	2,556,278
Indianapolis Power And Light Company [Member]
Debt Instrument [Line Items]
First mortgage bonds	1,780,673	1,780,410
Unamortized discount - net	(5,968)	(6,006)
Long-term debt	$ 1,780,673	1,780,410
Indianapolis Power And Light Company [Member] \| First Mortgage Bond 3.875% Due August 2021 [Member]
Debt Instrument [Line Items]
Debt, stated interest rate	3.875%
First mortgage bonds	$ 55,000	55,000
Indianapolis Power And Light Company [Member] \| First Mortgage Bond 3.875% Due August 2021 [Member]
Debt Instrument [Line Items]
Debt, stated interest rate	3.875%
First mortgage bonds	$ 40,000	40,000
Indianapolis Power And Light Company [Member] \| First Mortgage Bond 4.55% Due December 2024 [Member]
Debt Instrument [Line Items]
Debt, stated interest rate	3.125%
First mortgage bonds	$ 40,000	40,000
Indianapolis Power And Light Company [Member] \| First Mortgage Bond 6.60% Due January 2034 [Member]
Debt Instrument [Line Items]
Debt, stated interest rate	6.60%
First mortgage bonds	$ 100,000	100,000
Indianapolis Power And Light Company [Member] \| First Mortgage Bond 6.05% Due October 2036 [Member]
Debt Instrument [Line Items]
Debt, stated interest rate	6.05%
First mortgage bonds	$ 158,800	158,800
Indianapolis Power And Light Company [Member] \| First Mortgage Bond 6.60% Due June 2037 [Member]
Debt Instrument [Line Items]
Debt, stated interest rate	6.60%
First mortgage bonds	$ 165,000	165,000
Indianapolis Power And Light Company [Member] \| First Mortgage Bond 4.875% Due November 2041 [Member]
Debt Instrument [Line Items]
Debt, stated interest rate	4.875%
First mortgage bonds	$ 140,000	140,000
Indianapolis Power And Light Company [Member] \| First Mortgage Bond 4.65% Due June 2043 [Member]
Debt Instrument [Line Items]
Debt, stated interest rate	4.65%
First mortgage bonds	$ 170,000	170,000
Indianapolis Power And Light Company [Member] \| First Mortgage Bond 4.50% Due June 2044[Member]
Debt Instrument [Line Items]
Debt, stated interest rate	4.50%
First mortgage bonds	$ 130,000	130,000
Indianapolis Power And Light Company [Member] \| First Mortgage Bond 4.70%, Due September 2045 [Member]
Debt Instrument [Line Items]
Debt, stated interest rate	4.70%
First mortgage bonds	$ 260,000	260,000
Indianapolis Power And Light Company [Member] \| FMB Twenty [Member]
Debt Instrument [Line Items]
Debt, stated interest rate	4.05%
First mortgage bonds	$ 350,000	350,000
Indianapolis Power And Light Company [Member] \| FMB Twenty - one [Member]
Debt Instrument [Line Items]
Debt, stated interest rate	4.875%
First mortgage bonds	$ 105,000	105,000
Indianapolis Power And Light Company [Member] \| FMB Twenty - two
Debt Instrument [Line Items]
Debt, stated interest rate	0.75%
First mortgage bonds	$ 30,000	30,000
Indianapolis Power And Light Company [Member] \| FMB Twenty - three
Debt Instrument [Line Items]
Debt, stated interest rate	0.95%
First mortgage bonds	$ 60,000	60,000
Ipalco Enterprises, Inc. [Member]
Debt Instrument [Line Items]
Unamortized discount - net	(600)	(625)
Deferred financing costs	(8,280)	(8,600)
Net Consolidated IPALCO Long-term Debt	$ 871,120	870,775
Ipalco Enterprises, Inc. [Member] \| Three Point Seven Zero Percent Senior Secured Notes [Domain]
Debt Instrument [Line Items]
Debt, stated interest rate	3.70%
Long-term debt	$ 405,000	405,000
Ipalco Enterprises, Inc. [Member] \| Four Point Two Five Percent Senior Secured Notes
Debt Instrument [Line Items]
Debt, stated interest rate	4.25%
Long-term debt	$ 475,000	475,000
First Mortgage Bonds [Member] \| Indianapolis Power And Light Company [Member]
Debt Instrument [Line Items]
Deferred financing costs	$ (17,159)	$ (17,384)

Contractual interest rate for funds borrowed, under the debt agreement.

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Amount, after accumulated amortization, of debt discount.

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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Carrying value as of the balance sheet date, including the current and noncurrent portions, of collateralized debt obligations (with maturities initially due after one year or beyond the operating cycle, if longer). Such obligations include mortgage loans, chattel loans, and any other borrowings secured by assets of the borrower.

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