Revenue (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Jan. 31, 2018
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	$ 1,389,200		$ 1,326,600	$ 1,455,300
REVENUES	1,426,132	$ 1,352,985	1,481,643
Contract with Customer, Asset, before Allowance for Credit Loss			163,000		$ 163,800
Contract with Customer, Liability	0	500
Contract with Customer, Liability, Revenue Recognized	500	1,300
Contract with Customer, Liability	0	500
Contract with Customer, Liability, Revenue Recognized	500	1,300
Retail Revenue [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	1,351,431	1,269,319	1,375,533
Other non-606 revenue	35,248	24,781	23,841
Retail Revenue [Member] | Utility
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	16,785	14,402	14,136
Retail Revenue [Member] | Residential Revenue | Utility
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	595,692	566,668	589,719
Retail Revenue [Member] | Small Commercial and Industrial | Utility
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	211,997	194,904	215,878
Retail Revenue [Member] | Large Commercial and Industrial | Utility
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	518,069	484,230	548,551
Retail Revenue [Member] | Public Lighting | Utility
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	8,888	9,115	7,249
Wholesale Revenue [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	25,059	46,482	68,474
Miscellaneous revenue [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	12,671	10,794	11,335
Other non-606 revenue	1,723	1,609	2,460
Electricity [Member]
Disaggregation of Revenue [Line Items]
REVENUES	1,426,132	1,352,985	1,481,643
Indianapolis Power And Light Company
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	1,389,200	1,326,600	1,455,300
REVENUES	1,426,132	1,352,985	1,481,643
Contract with Customer, Asset, before Allowance for Credit Loss			163,000		$ 163,800
Contract with Customer, Liability	0	500
Contract with Customer, Liability, Revenue Recognized	500	1,300
Contract with Customer, Liability	0	500
Contract with Customer, Liability, Revenue Recognized	500	1,300
Indianapolis Power And Light Company | Retail Revenue [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	1,351,431	1,269,319	1,375,533
Other non-606 revenue	35,248	24,781	23,841
Indianapolis Power And Light Company | Retail Revenue [Member] | Utility
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	16,785	14,402	14,136
Indianapolis Power And Light Company | Retail Revenue [Member] | Residential Revenue | Utility
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	595,692	566,668	589,719
Indianapolis Power And Light Company | Retail Revenue [Member] | Small Commercial and Industrial | Utility
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	211,997	194,904	215,878
Indianapolis Power And Light Company | Retail Revenue [Member] | Large Commercial and Industrial | Utility
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	518,069	484,230	548,551
Indianapolis Power And Light Company | Retail Revenue [Member] | Public Lighting | Utility
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	8,888	9,115	7,249
Indianapolis Power And Light Company | Wholesale Revenue [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	25,059	46,482	68,474
Indianapolis Power And Light Company | Miscellaneous revenue [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	12,671	10,794	11,335
Other non-606 revenue	1,723	1,609	2,460
Indianapolis Power And Light Company | Electricity [Member]
Disaggregation of Revenue [Line Items]
REVENUES	$ 1,426,132	$ 1,352,985	$ 1,481,643