Organization (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012 MW customer	Dec. 31, 2011
Number of customers	470,000
Electric generation capability for winter, megawatts	3,492
Electric generation capability for summer, megawatts	3,353
Oustanding Receivables Purchased Amount	$ 50	$ 50
Indianapolis Power And Light Company [Member]
Number of customers	470,000
Electric generation capability for winter, megawatts	3,492
Electric generation capability for summer, megawatts	3,353
Oustanding Receivables Purchased Amount	$ 50	$ 50