Benefit Plans (Information For Pension Plans With A Benefit Obligation In Excess Of Plan Assets) (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Entity Information [Line Items]
Defined Benefit Plan, Pension Plan with Projected Benefit Obligation in Excess of Plan Assets, Plan Assets	$ 820,700
Benefit obligation in excess of plan assets	(48,644)	$ (7,495)
Indianapolis Power And Light Company
Entity Information [Line Items]
Defined Benefit Plan, Pension Plan with Projected Benefit Obligation in Excess of Plan Assets, Projected Benefit Obligation	772,000
Benefit obligation in excess of plan assets	$ (48,644)	$ (7,495)