Redeemable Stocks of Subsidiaries (Details) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Temporary Equity [Line Items]
Redeemable Noncontrolling Interest, Equity, Carrying Amount		$ 873		$ 888
Colon [Domain]
Temporary Equity [Line Items]
Temporary Equity, Other Charges		0	$ 10
Redeemable Noncontrolling Interest, Equity, Common, Carrying Amount	[1]	195		210
IPALCO Enterprises, Inc. [Member]
Temporary Equity [Line Items]
Redeemable Noncontrolling Interest, Equity, Common, Carrying Amount		618		618
IPL Subsidiary [Member]
Temporary Equity [Line Items]
Redeemable Noncontrolling Interest, Equity, Preferred, Carrying Amount		$ 60		$ 60

[1] Characteristics of quotas are similar to common stock.