Income Taxes (Schedule Of Federal And State Income Taxed Charged To Income) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Taxes [Line Items]
Income Tax Expense (Benefit), Total	$ 35,528	$ 13,449	$ 48,951
Charged To Utility Operating Expense [Member]
Income Taxes [Line Items]
Current income taxes, Federal	17,229	20,341	42,542
Current income taxes, State	3,022	8,843	9,916
Total current income taxes	20,251	29,184	52,458
Deferred income taxes, Federal	7,547	(15,150)	(1,720)
Deferred income taxes, State	7,745	326	(332)
Total deferred income taxes	15,292	(14,824)	(2,052)
Net amortization of investment credit	(15)	(911)	(1,455)
Income Tax Expense (Benefit), Total	35,528	13,449	48,951
Indianapolis Power And Light Company
Income Taxes [Line Items]
Income Tax Expense (Benefit), Total	43,430	21,590	65,591
Indianapolis Power And Light Company | Charged To Utility Operating Expense [Member]
Income Taxes [Line Items]
Current income taxes, Federal	23,941	26,021	56,377
Current income taxes, State	4,370	11,215	12,656
Total current income taxes	28,311	37,236	69,033
Deferred income taxes, Federal	7,578	(15,080)	(1,634)
Deferred income taxes, State	7,556	345	(353)
Total deferred income taxes	15,134	(14,735)	(1,987)
Net amortization of investment credit	(15)	(911)	(1,455)
Income Tax Expense (Benefit), Total	$ 43,430	$ 21,590	$ 65,591