XML 175 R108.htm IDEA: XBRL DOCUMENT
v3.22.4

Supplemental Information (Allowance for Doubtful Accounts) (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2022 | Dec. 31, 2021
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Beginning balance at January 1 | $ 29 | $ 50
Bad debt expense | 38 | 9
Net write-offs | (36) | (30)
Ending balance at December 31 | $ 31 | $ 29
Percentage of accounts receivable balances that are 30 days past due or are part of a deferred payment arrangement | 17.00% | 20.00%
Accounts receivable balances that are 30 days or more past due or part of a deferred payment arrangement | $ 107 | $ 94
Union Electric Company |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Beginning balance at January 1 | 13 | 16
Bad debt expense | 9 | 5
Net write-offs | (9) | (8)
Ending balance at December 31 | $ 13 | $ 13
Percentage of accounts receivable balances that are 30 days past due or are part of a deferred payment arrangement | 14.00% | 17.00%
Accounts receivable balances that are 30 days or more past due or part of a deferred payment arrangement | $ 35 | $ 34
Ameren Illinois Company |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Beginning balance at January 1 | 16 | 34
Bad debt expense | 29 | 4
Net write-offs | (27) | (22)
Ending balance at December 31 | $ 18 | $ 16
Percentage of accounts receivable balances that are 30 days past due or are part of a deferred payment arrangement | 20.00% | 24.00%
Accounts receivable balances that are 30 days or more past due or part of a deferred payment arrangement | $ 71 | $ 60

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 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 Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
Name: | us-gaap_AccountsNotesAndLoansReceivableLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

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 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: |