XML 30 R10.htm IDEA: XBRL DOCUMENT v3.24.2.u1
Investments
 6 Months Ended
Jun. 30, 2024
Schedule of Equity Method Investments [Line Items]  
Investments INVESTMENTS
Unconsolidated Equity Investments - Alliant Energy’s equity (income) loss from unconsolidated investments accounted for under the equity method of accounting for the three and six months ended June 30 was as follows (in millions):
Three MonthsSix Months
2024202320242023
ATC Holdings($13)($12)($25)($25)
Other(2)(2)(6)(6)
($15)($14)($31)($31)