Schedule I - Condensed Financial Information Of Registrant (Long-Term Indebtedness) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011
Condensed Financial Statements, Captions [Line Items]
Long-term debt	$ 1,761,120	$ 1,760,316
Unamortized discount - net	(4,200)	(5,000)
Less: Current Portion of Long-term Debt	110,000
Long-term debt	1,651,120	1,760,316
Ipalco Enterprises, Inc. [Member]
Condensed Financial Statements, Captions [Line Items]
Long-term debt	796,916	796,141
Unamortized discount - net	(3,084)	(3,859)
Long-term debt	796,916	796,141
Ipalco Enterprises, Inc. [Member] | 7.250% Senior Secured Notes [Member]
Condensed Financial Statements, Captions [Line Items]
Long-term debt	400,000	400,000
Debt, stated interest rate	7.25%
Debt due date	Apr. 01, 2016
Ipalco Enterprises, Inc. [Member] | 5.000% Senior Secured Notes [Member]
Condensed Financial Statements, Captions [Line Items]
Long-term debt	$ 400,000	$ 400,000
Debt, stated interest rate	5.00%
Debt due date	May 01, 2018