XML 186 R113.htm IDEA: XBRL DOCUMENT v3.25.4
Supplemental Information (Leases) (Details) - USD ($)
$ in Millions
Dec. 31, 2025
Dec. 31, 2024
Schedule of Supplemental Balance Sheet Information Related to Operating Leases [Line Items]    
Operating Lease, Right-of-Use Asset $ 76 $ 72
Operating Lease, Right-of-Use Asset, Statement of Financial Position [Extensible Enumeration] Other assets Other assets
Operating Lease, Liability, Current $ 3 $ 5
Operating Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration] Other current liabilities Other current liabilities
Operating Lease, Liability, Noncurrent $ 73 $ 67
Operating Lease, Liability, Noncurrent, Statement of Financial Position [Extensible Enumeration] Other deferred credits and liabilities Other deferred credits and liabilities
Operating Lease, Weighted Average Remaining Lease Term 28 years 29 years
Operating Lease, Weighted Average Discount Rate, Percent 5.30% 5.30%
Lessee, Operating Lease, Liability, to be Paid, Maturity [Line Items]    
2026 $ 6  
2027 6  
2028 6  
2029 6  
2030 5  
Thereafter 129  
Total lease payments 158  
Less imputed interest 82  
Total 76  
Ameren Missouri    
Schedule of Supplemental Balance Sheet Information Related to Operating Leases [Line Items]    
Operating Lease, Right-of-Use Asset 70 $ 69
Operating Lease, Liability, Current 2 4
Operating Lease, Liability, Noncurrent $ 68 $ 65
Operating Lease, Weighted Average Remaining Lease Term 29 years 30 years
Operating Lease, Weighted Average Discount Rate, Percent 5.30% 5.30%
Lessee, Operating Lease, Liability, to be Paid, Maturity [Line Items]    
2026 $ 5  
2027 5  
2028 5  
2029 5  
2030 4  
Thereafter 127  
Total lease payments 151  
Less imputed interest 81  
Total $ 70