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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 |

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