Overview and Summary of Significant Accounting Policies Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2015

Entity Information [Line Items]

Schedule of Expected Service and Interest Costs

The impact of the change in approach on expected service costs in 2016 is shown below:

$ in thousands	Expected 2016 Service Cost							Expected 2016 Interest Cost
	Disaggregated rate approach		Aggregate rate approach		Impact of change			Disaggregated rate approach		Aggregate rate approach		Impact of change
Pension	$	7,018	$	7,382	$	(364	)	$	25,634	$	30,916	$	(5,282	)

Indianapolis Power And Light Company [Member]

Entity Information [Line Items]

Schedule of Expected Service and Interest Costs

The impact of the change in approach on expected service costs in 2016 is shown below:

$ in thousands	Expected 2016 Service Cost							Expected 2016 Interest Cost
	Disaggregated rate approach		Aggregate rate approach		Impact of change			Disaggregated rate approach		Aggregate rate approach		Impact of change
Pension	$	7,018	$	7,382	$	(364	)	$	25,634	$	30,916	$	(5,282	)