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v3.22.2.2

Supplemental Information (Allowance for Doubtful Accounts) (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2022 | Sep. 30, 2021 | Sep. 30, 2022 | Sep. 30, 2021 | Dec. 31, 2021
Allowance for Doubtful Accounts Receivable [Roll Forward] |  |  |  |  |
Beginning of period | $ 30 | $ 42 | $ 29 | $ 50 |
Bad debt expense | 15 | 7 | 26 | 8 |
Net write-offs | (14) | (13) | (24) | (22) |
End of period | 31 | $ 36 | 31 | $ 36 |
Payables for purchased receivables | $ 32 |  | $ 32 |  | $ 27
Percentage of accounts receivable balances that are 30 days past due or are part of a deferred payment arrangement | 17.00% | 18.00% | 17.00% | 18.00% |
Accounts receivable balances that are 30 days or more past due or part of a deferred payment arrangement | $ 117 | $ 97 | $ 117 | $ 97 |
Union Electric Company |  |  |  |  |
Allowance for Doubtful Accounts Receivable [Roll Forward] |  |  |  |  |
Beginning of period | 12 | 16 | 13 | 16 |
Bad debt expense | 3 | 2 | 6 | 5 |
Net write-offs | (3) | (4) | (7) | (7) |
End of period | $ 12 | $ 14 | $ 12 | $ 14 |
Percentage of accounts receivable balances that are 30 days past due or are part of a deferred payment arrangement | 12.00% | 12.00% | 12.00% | 12.00% |
Accounts receivable balances that are 30 days or more past due or part of a deferred payment arrangement | $ 39 | $ 33 | $ 39 | $ 33 |
Ameren Illinois Company |  |  |  |  |
Allowance for Doubtful Accounts Receivable [Roll Forward] |  |  |  |  |
Beginning of period | 18 | 26 | 16 | 34 |
Bad debt expense | 12 | 5 | 20 | 3 |
Net write-offs | (11) | (9) | (17) | (15) |
End of period | 19 | $ 22 | 19 | $ 22 |
Payables for purchased receivables | $ 32 |  | $ 32 |  | $ 27
Percentage of accounts receivable balances that are 30 days past due or are part of a deferred payment arrangement | 21.00% | 25.00% | 21.00% | 25.00% |
Accounts receivable balances that are 30 days or more past due or part of a deferred payment arrangement | $ 78 | $ 64 | $ 78 | $ 64 |

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- Definition Percentage of accounts receivable balances that are 30 days past due or are part of a deferred payment arrangement + References No definition available. + Details
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