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v3.25.1

Supplemental Information (Allowance for Doubtful Accounts) (Details) - USD ($) $ in Millions | 3 Months Ended |
--- | --- | ---
Mar. 31, 2025 | Mar. 31, 2024 | Dec. 31, 2024
Allowance for Doubtful Accounts Receivable [Roll Forward] |  |  |
Beginning of period | $ 30 | $ 30 |
Bad debt expense | 16 | 10 |
Charged to other accounts | 1 | 3 |
Net write-offs | (6) | (6) |
End of period | 41 | 37 |
Payables for purchased receivables | 47 |  | $ 43
Union Electric Company |  |  |
Allowance for Doubtful Accounts Receivable [Roll Forward] |  |  |
Beginning of period | 12 | 12 |
Bad debt expense | 2 | 1 |
Net write-offs | (2) | (2) |
End of period | 12 | 11 |
Ameren Illinois Company |  |  |
Allowance for Doubtful Accounts Receivable [Roll Forward] |  |  |
Beginning of period | 18 | 18 |
Bad debt expense | 14 | 9 |
Charged to other accounts | 1 | 3 |
Net write-offs | (4) | (4) |
End of period | 29 | $ 26 |
Payables for purchased receivables | $ 47 |  | $ 43

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