XML 92 R60.htm IDEA: XBRL DOCUMENT
v3.23.1

Supplemental Information (Allowance for Doubtful Accounts) (Details) - USD ($) $ in Millions | 3 Months Ended |
--- | --- | ---
Mar. 31, 2023 | Mar. 31, 2022 | Dec. 31, 2022
Allowance for Doubtful Accounts Receivable [Roll Forward] |  |  |
Beginning of period | $ 31 | $ 29 |
Bad debt expense | 10 | 4 |
Net write-offs | (7) | (5) |
End of period | 34 | $ 28 |
Payables for purchased receivables | $ 35 |  | $ 31
Percentage of accounts receivable balances that are 30 days past due or are part of a deferred payment arrangement | 23.00% | 20.00% |
Accounts receivable balances that are 30 days or more past due or part of a deferred payment arrangement | $ 153 | $ 116 |
Union Electric Company |  |  |
Allowance for Doubtful Accounts Receivable [Roll Forward] |  |  |
Beginning of period | 13 | 13 |
Bad debt expense | 2 | 1 |
Net write-offs | (3) | (3) |
End of period | $ 12 | $ 11 |
Percentage of accounts receivable balances that are 30 days past due or are part of a deferred payment arrangement | 15.00% | 15.00% |
Accounts receivable balances that are 30 days or more past due or part of a deferred payment arrangement | $ 33 | $ 31 |
Ameren Illinois Company |  |  |
Allowance for Doubtful Accounts Receivable [Roll Forward] |  |  |
Beginning of period | 18 | 16 |
Bad debt expense | 8 | 3 |
Net write-offs | (4) | (2) |
End of period | 22 | $ 17 |
Payables for purchased receivables | $ 35 |  | $ 31
Percentage of accounts receivable balances that are 30 days past due or are part of a deferred payment arrangement | 28.00% | 23.00% |
Accounts receivable balances that are 30 days or more past due or part of a deferred payment arrangement | $ 120 | $ 85 |

X
- Definition Accounts receivable balances that are 30 days or more past due or part of a deferred payment arrangement + References No definition available. + Details
Name: | aee_AccountsReceivableBalancesThatAre30DaysOrMorePastDueOrPartOfADeferredPaymentArrangement
Namespace Prefix: | aee_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of liabilties for purchased receivables + References No definition available. + Details
Name: | aee_Payablesforpurchasedreceivables
Namespace Prefix: | aee_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- 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
Name: | aee_PercentageOfAccountsReceivableBalancesThatAre30DaysPastDueOrArePartOfADeferredPaymentArrangement
Namespace Prefix: | aee_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Amount of allowance for credit loss on accounts receivable. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 13 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=123577603&loc=d3e5074-111524 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 13 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=124255206&loc=SL82895884-210446 + Details
Name: | us-gaap_AllowanceForDoubtfulAccountsReceivable
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. + References No definition available. + Details
Name: | us-gaap_AllowanceForDoubtfulAccountsReceivableRollforward
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of direct write-downs of accounts receivable charged against the allowance. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 13 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447 + Details
Name: | us-gaap_AllowanceForDoubtfulAccountsReceivableWriteOffs
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of expense (reversal of expense) for expected credit loss on accounts receivable. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 13 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03(5)) -URI http://asc.fasb.org/extlink&oid=123367319&loc=SL114868664-224227 + Details
Name: | us-gaap_ProvisionForDoubtfulAccounts
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Details
Name: | dei_LegalEntityAxis=aee_UnionElectricCompanyMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | dei_LegalEntityAxis=aee_AmerenIllinoisCompanyMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |