XML 47 R27.htm IDEA: XBRL DOCUMENT v3.24.2.u1
Investments (Tables)
 6 Months Ended
Jun. 30, 2024
Schedule of Equity Method Investments [Line Items]  
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)