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

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

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The amount of debt discount that was originally recognized at the issuance of the instrument that has yet to be amortized.

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Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount of long-term debt, after unamortized discount or premium, scheduled 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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Debt (Schedule Long-Term Indebtedness) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Dec. 31, 2014	Jun. 30, 2014	Jun. 30, 2013
Debt Instrument [Line Items]
Unamortized discount - net	$ (4,600)			$ (4,300)
Long-term debt	2,173,837			1,951,013
Current portion of long-term debt	0			0
Long-term debt	2,173,837			1,951,013
Ipalco Enterprises, Inc. [Member]
Debt Instrument [Line Items]
Unamortized discount - net	(371)			(1,347)
Long-term debt	804,629			798,653
Current portion of long-term debt	0			0
Long-term debt	804,629			798,653
Ipalco Enterprises, Inc. [Member] \| 7.25% Senior Secured Notes [Member]
Debt Instrument [Line Items]
Long-term debt	$ 0		$ 33,500	400,000
Debt, stated interest rate	7.25%
Debt due date	Apr. 01, 2016
Ipalco Enterprises, Inc. [Member] \| 5.00% Senior Secured Notes [Member]
Debt Instrument [Line Items]
Long-term debt	$ 400,000			400,000
Debt, stated interest rate	5.00%
Debt due date	May 01, 2018
Ipalco Enterprises, Inc. [Member] \| 3.45% Senior Secured Notes [Member]
Debt Instrument [Line Items]
Long-term debt	$ 405,000			0
Debt, stated interest rate	3.45%
Debt due date	Jul. 01, 2020
Indianapolis Power And Light Company [Member]
Debt Instrument [Line Items]
First mortgage bonds	$ 1,279,208			1,152,360
Unamortized discount - net	(4,242)			(2,940)
Unsecured Debt	90,000			0
Long-term debt	1,369,208			1,152,360
Current portion of long-term debt	0			0
Long-term debt	1,369,208			1,152,360
Indianapolis Power And Light Company [Member] \| First Mortgage Bond 4.90% Due January 2016 [Member]
Debt Instrument [Line Items]
First mortgage bonds	$ 0			30,000
Debt, stated interest rate	4.90%
Debt due date	Jan. 01, 2016
Indianapolis Power And Light Company [Member] \| First Mortgage Bond 4.90% Due January 2016 [Member]
Debt Instrument [Line Items]
First mortgage bonds	$ 0			41,850
Debt, stated interest rate	4.90%
Debt due date	Jan. 01, 2016
Indianapolis Power And Light Company [Member] \| First Mortgage Bond 4.90% Due January 2016 [Member]
Debt Instrument [Line Items]
First mortgage bonds	$ 0			60,000
Debt, stated interest rate	4.90%
Debt due date	Jan. 01, 2016
Indianapolis Power And Light Company [Member] \| First Mortgage Bond 5.40% Due August 2017 [Member]
Debt Instrument [Line Items]
First mortgage bonds	$ 24,650			24,650
Debt, stated interest rate	5.40%
Debt due date	Aug. 01, 2017
Indianapolis Power And Light Company [Member] \| 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 [Member] \| 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 [Member] \| First Mortgage Bond 4.55% Due December 2024 [Member]
Debt Instrument [Line Items]
First mortgage bonds	$ 40,000			40,000
Debt, stated interest rate	4.55%
Debt due date	Dec. 01, 2024
Indianapolis Power And Light Company [Member] \| 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 [Member] \| 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 [Member] \| 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 [Member] \| 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 [Member] \| 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%					4.65%
Debt due date	Jun. 01, 2043
Indianapolis Power And Light Company [Member] \| First Mortgage Bond Nineteen [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 [Member] \| First Mortgage Bond 4.70% Due September 2045 [Member]
Debt Instrument [Line Items]
First mortgage bonds	$ 260,000			0
Debt, stated interest rate	4.70%	4.70%			4.50%
Debt due date	Sep. 01, 2045
Indianapolis Power And Light Company [Member] \| Environmental Facilities Refunding Revenue Notes, Series 2015A [Member]
Debt Instrument [Line Items]
Unsecured Debt	$ 30,000			0
Debt due date	Dec. 01, 2020
Indianapolis Power And Light Company [Member] \| Environmental Facilities Refunding Revenue Notes, Series 2015B [Member]
Debt Instrument [Line Items]
Unsecured Debt	$ 60,000			$ 0
Debt due date	Dec. 01, 2020