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

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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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.

+ References

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

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Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. 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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Including the current and noncurrent portions, carrying value as of the balance sheet date of uncollateralized debt obligations (with maturities initially due after one year or beyond the operating cycle if longer).

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Debt (Schedule Long-Term Indebtedness) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Dec. 31, 2018	Nov. 14, 2018	Oct. 31, 2018	Aug. 22, 2017
Debt Instrument [Line Items]
Unamortized discount - net	$ (6,500)		$ (6,700)
Debt Issuance Costs, Net	(20,700)		(23,000)
Long-term debt	2,651,629		2,649,064
Current portion of long-term debt	559,199		0
Long-term debt	2,092,430		2,649,064
Ipalco Enterprises, Inc. [Member]
Debt Instrument [Line Items]
Unamortized discount - net	(313)		(424)
Debt Issuance Costs, Net	(3,959)		(5,696)
Long-term debt	870,728		868,880
Current portion of long-term debt	469,313		0
Long-term debt	401,415		868,880
Ipalco Enterprises, Inc. [Member] \| Bank Term Loan Maturing July 2020 [Member]
Debt Instrument [Line Items]
Long-term debt	$ 65,000	$ 65,000	65,000		$ 65,000
Debt due date	Jul. 01, 2020
Ipalco Enterprises, Inc. [Member] \| 7.25% Senior Secured Notes [Member]
Debt Instrument [Line Items]
Debt, stated interest rate	7.25%
Ipalco Enterprises, Inc. [Member] \| 5.00% Senior Secured Notes [Member]
Debt Instrument [Line Items]
Debt, stated interest rate	5.00%
Ipalco Enterprises, Inc. [Member] \| 3.45% Senior Secured Notes [Member]
Debt Instrument [Line Items]
Long-term debt	$ 405,000	$ 405,000	405,000
Debt, stated interest rate	3.45%	3.45%
Debt due date	Jul. 01, 2020
Ipalco Enterprises, Inc. [Member] \| Three Point Seven Zero Percent Senior Secured Notes [Domain]
Debt Instrument [Line Items]
Long-term debt	$ 405,000		405,000			$ 405,000
Debt, stated interest rate	3.70%
Debt due date	Sep. 01, 2024
Indianapolis Power And Light Company
Debt Instrument [Line Items]
First mortgage bonds	$ 1,691,015		1,690,413
Unamortized discount - net	(6,156)		(6,272)
Debt Issuance Costs, Net	(16,700)		(17,300)
Unsecured Debt	89,886		89,771
Long-term debt	1,780,901		1,780,184
Current portion of long-term debt	89,886		0
Long-term debt	$ 1,691,015		1,780,184
Indianapolis Power And Light Company \| First Mortgage Bond 5.40% Due August 2017 [Member]
Debt Instrument [Line Items]
Debt, stated interest rate	5.40%
Indianapolis Power And Light Company \| First Mortgage Bond 3.875% Due August 2021 [Member]
Debt Instrument [Line Items]
First mortgage bonds	$ 55,000		55,000
Debt, stated interest rate	3.875%
Debt due date	Aug. 01, 2021
Indianapolis Power And Light Company \| First Mortgage Bond 3.875% Due August 2021 [Member]
Debt Instrument [Line Items]
First mortgage bonds	$ 40,000		40,000
Debt, stated interest rate	3.875%
Debt due date	Aug. 01, 2021
Indianapolis Power And Light Company \| First Mortgage Bond 4.55% Due December 2024 [Member]
Debt Instrument [Line Items]
First mortgage bonds	$ 40,000		40,000
Debt, stated interest rate	3.125%
Debt due date	Dec. 01, 2024
Indianapolis Power And Light Company \| First Mortgage Bond 6.60% Due January 2034 [Member]
Debt Instrument [Line Items]
First mortgage bonds	$ 100,000		100,000
Debt, stated interest rate	6.60%
Debt due date	Jan. 01, 2034
Indianapolis Power And Light Company \| First Mortgage Bond 6.05% Due October 2036 [Member]
Debt Instrument [Line Items]
First mortgage bonds	$ 158,800		158,800
Debt, stated interest rate	6.05%
Debt due date	Oct. 01, 2036
Indianapolis Power And Light Company \| First Mortgage Bond 6.60% Due June 2037 [Member]
Debt Instrument [Line Items]
First mortgage bonds	$ 165,000		165,000
Debt, stated interest rate	6.60%
Debt due date	Jun. 01, 2037
Indianapolis Power And Light Company \| First Mortgage Bond 4.875% Due November 2041 [Member]
Debt Instrument [Line Items]
First mortgage bonds	$ 140,000		140,000
Debt, stated interest rate	4.875%
Debt due date	Nov. 01, 2041
Indianapolis Power And Light Company \| First Mortgage Bond 4.65% Due June 2043 [Member]
Debt Instrument [Line Items]
First mortgage bonds	$ 170,000		170,000
Debt, stated interest rate	4.65%
Debt due date	Jun. 01, 2043
Indianapolis Power And Light Company \| First Mortgage Bond 4.70% Due September 2045 [Member]
Debt Instrument [Line Items]
First mortgage bonds	$ 130,000		130,000
Debt, stated interest rate	4.50%
Debt due date	Jun. 01, 2044
Indianapolis Power And Light Company \| First Mortgage Bond Nineteen [Member]
Debt Instrument [Line Items]
First mortgage bonds	$ 260,000		260,000
Debt, stated interest rate	4.70%
Debt due date	Sep. 01, 2045
Indianapolis Power And Light Company \| FMB Twenty [Member]
Debt Instrument [Line Items]
First mortgage bonds	$ 350,000		350,000
Debt, stated interest rate	4.05%
Debt due date	May 01, 2046
Indianapolis Power And Light Company \| FMB Twenty - one [Member]
Debt Instrument [Line Items]
First mortgage bonds	$ 105,000		105,000
Debt, stated interest rate	4.875%			4.875%
Debt due date	Nov. 01, 2048
Indianapolis Power And Light Company \| Environmental Facilities Refunding Revenue Notes, Series 2015A [Member]
Debt Instrument [Line Items]
Unsecured Debt	$ 30,000		30,000
Debt due date	Dec. 22, 2020
Indianapolis Power And Light Company \| Environmental Facilities Refunding Revenue Notes, Series 2015B [Member]
Debt Instrument [Line Items]
Unsecured Debt	$ 60,000		60,000
Debt due date	Dec. 22, 2020
Secured Debt [Member] \| Indianapolis Power And Light Company
Debt Instrument [Line Items]
Unamortized discount - net	$ (6,156)
Debt Issuance Costs, Net	(16,629)		(17,115)
Unsecured Debt [Member] \| Indianapolis Power And Light Company
Debt Instrument [Line Items]
Debt Issuance Costs, Net	$ (114)		$ (229)