XML 189 R122.htm IDEA: XBRL DOCUMENT
v3.22.4

Schedule II - Valuation And Qualifying Accounts (Details) - Allowance For Doubtful Accounts - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items] |  |  |
Balance at Beginning of Period | $ 29 | $ 50 | $ 17
Charged to Costs and Expenses | 34 | 9 | 42
Charged to Other Accounts | 4 | 0 | 6
Deductions | 36 | 30 | 15
Balance at End of Period | 31 | 29 | 50
Union Electric Company |  |  |
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items] |  |  |
Balance at Beginning of Period | 13 | 16 | 7
Charged to Costs and Expenses | 9 | 5 | 15
Charged to Other Accounts | 0 | 0 | 0
Deductions | 9 | 8 | 6
Balance at End of Period | 13 | 13 | 16
Ameren Illinois Company |  |  |
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items] |  |  |
Balance at Beginning of Period | 16 | 34 | 10
Charged to Costs and Expenses | 25 | 4 | 27
Charged to Other Accounts | 4 | 0 | 6
Deductions | 27 | 22 | 9
Balance at End of Period | $ 18 | $ 16 | $ 34

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: | srt_ValuationAndQualifyingAccountsDisclosureLineItems
Namespace Prefix: | srt_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of valuation and qualifying accounts and reserves. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 4 -Subparagraph (SX 210.12-09(Column B)) -URI http://asc.fasb.org/extlink&oid=120395691&loc=d3e24092-122690 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 4 -Subparagraph (SX 210.12-09(Column E)) -URI http://asc.fasb.org/extlink&oid=120395691&loc=d3e24092-122690 + Details
Name: | us-gaap_ValuationAllowancesAndReservesBalance
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of increase in valuation and qualifying accounts and reserves from charge to cost and expense. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 4 -Subparagraph (SX 210.12-09(Column C)(1)) -URI http://asc.fasb.org/extlink&oid=120395691&loc=d3e24092-122690 + Details
Name: | us-gaap_ValuationAllowancesAndReservesChargedToCostAndExpense
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount of increase in valuation and qualifying accounts and reserves from charge to accounts other than cost and expense. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 4 -Subparagraph (SX 210.12-09(Column C)(2)) -URI http://asc.fasb.org/extlink&oid=120395691&loc=d3e24092-122690 + Details
Name: | us-gaap_ValuationAllowancesAndReservesChargedToOtherAccounts
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount of decrease in valuation and qualifying accounts and reserves. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 4 -Subparagraph (SX 210.12-09(Column D)) -URI http://asc.fasb.org/extlink&oid=120395691&loc=d3e24092-122690 + Details
Name: | us-gaap_ValuationAllowancesAndReservesDeductions
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Details
Name: | us-gaap_ValuationAllowancesAndReservesTypeAxis=us-gaap_AllowanceForCreditLossMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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: |