XML 79 R40.htm IDEA: XBRL DOCUMENT
v3.22.2.2

Long-Term debt and Equity Financings (Details) $ / shares in Units, shares in Millions | 1 Months Ended | 3 Months Ended | 9 Months Ended |  |
--- | --- | --- | --- | --- | ---
Aug. 31, 2022 USD ($) | Apr. 30, 2022 USD ($) | Sep. 30, 2022 USD ($) shares | Mar. 31, 2022 USD ($) shares | Sep. 30, 2021 shares | Sep. 30, 2022 USD ($) $ / shares shares | Sep. 30, 2021 USD ($) shares | Aug. 29, 2022 USD ($) | May 31, 2021 USD ($)
Long-Term Debt And Equity Financings [Line Items] |  |  |  |  |  |  |  |  |
Shares issued under the DRPlus and 401(k) plan | shares |  |  | 0.1 |  | 0.1 | 0.4 | 0.4 |  |
Issuances of common stock |  |  |  |  |  | $ 29,000,000 | $ 297,000,000 |  |
Stock Issued During Period, Shares, Other | shares |  |  | 0.0 | 0.4 | 0.0 | 0.4 | 0.5 |  |
Stock Issued During Period, Value, Other |  |  |  | $ 31,000,000 |  |  |  |  |
Maximum Value Of Shares To Be Issued Under ATM Program |  |  |  |  |  |  |  |  | $ 750,000,000
Forward Contract Indexed to Issuer's Equity, Basis Spread |  |  | 75 |  |  | 75 |  |  |
Minimum |  |  |  |  |  |  |  |  |
Long-Term Debt And Equity Financings [Line Items] |  |  |  |  |  |  |  |  |
Forward Contract Indexed to Issuer's Equity, Forward Rate Per Share | $ / shares |  |  |  |  |  | $ 86.35 |  |  |
Maximum |  |  |  |  |  |  |  |  |
Long-Term Debt And Equity Financings [Line Items] |  |  |  |  |  |  |  |  |
Forward Contract Indexed to Issuer's Equity, Forward Rate Per Share | $ / shares |  |  |  |  |  | 94.80 |  |  |
Weighted Average |  |  |  |  |  |  |  |  |
Long-Term Debt And Equity Financings [Line Items] |  |  |  |  |  |  |  |  |
Forward Contract Indexed to Issuer's Equity, Forward Rate Per Share | $ / shares |  |  |  |  |  | $ 90.31 |  |  |
Dividend reinvestment and 401 (k) plans |  |  |  |  |  |  |  |  |
Long-Term Debt And Equity Financings [Line Items] |  |  |  |  |  |  |  |  |
Issuances of common stock |  |  | $ 4,000,000 |  |  | $ 29,000,000 |  |  |
Accrued Proceeds from Issuance of Common Stock |  |  |  |  |  | $ 8,000,000 |  |  |
Forward Sale Agreements Outstanding |  |  |  |  |  |  |  |  |
Long-Term Debt And Equity Financings [Line Items] |  |  |  |  |  |  |  |  |
Forward Contract Indexed to Issuer's Equity, Indexed Shares (in shares) | shares |  |  | 6.6 |  |  | 6.6 |  |  |
Forward Contract Indexed to Issuer's Equity, Settlement Alternatives, Shares, at Fair Value | shares |  |  | 6.6 |  |  | 6.6 |  |  |
Forward Contract Indexed to Issuer's Equity, Settlement Alternatives, Cash, at Fair Value |  |  | $ 587,000,000 |  |  | $ 587,000,000 |  |  |
Period End Net Cash Settlement Price |  |  | 58,000,000 |  |  | 58,000,000 |  |  |
Period End Net Share Settlement Price |  |  | 700,000 |  |  | 700,000 |  |  |
Forward Sale Agreement Equity Offering Shares |  |  | 6,600,000 |  |  | 6,600,000 |  |  |
Forward Sale Agreement Gross Sales Price |  |  | 600,000,000 |  |  | 600,000,000 |  |  |
Forward Sale Agreement, Compensation Received by Counterparty |  |  | $ 6,000,000 |  |  | $ 6,000,000 |  |  |
Union Electric Company | Secured Debt | Senior Secured Notes 3.90% Due 2052 |  |  |  |  |  |  |  |  |
Long-Term Debt And Equity Financings [Line Items] |  |  |  |  |  |  |  |  |
Debt Instrument, Face Amount |  | $ 525,000,000 |  |  |  |  |  |  |
Debt Instrument, Interest Rate, Stated Percentage |  | 3.90% |  |  |  |  |  |  |
Proceeds from Issuance of Secured Debt |  | $ 519,000,000 |  |  |  |  |  |  |
Ameren Illinois Company | Unsecured Debt | Senior Secured Notes 3.85% Due 2032 |  |  |  |  |  |  |  |  |
Long-Term Debt And Equity Financings [Line Items] |  |  |  |  |  |  |  |  |
Debt Instrument, Face Amount |  |  |  |  |  |  |  | $ 500,000,000 |
Debt Instrument, Interest Rate, Stated Percentage |  |  |  |  |  |  |  | 3.85% |
Proceeds from Issuance of Secured Debt | $ 496,000,000 |  |  |  |  |  |  |  |
Ameren Illinois Company | Unsecured Debt | Senior Secured Notes 2.70% Due 2022 |  |  |  |  |  |  |  |  |
Long-Term Debt And Equity Financings [Line Items] |  |  |  |  |  |  |  |  |
Debt Instrument, Face Amount |  |  |  |  |  |  |  | $ 400,000,000 |
Debt Instrument, Interest Rate, Stated Percentage |  |  |  |  |  |  |  | 2.70% |
Ameren Transmission Company of Illinois | Unsecured Debt | Senior Unsecured Notes, 2.96%, Due 2052 |  |  |  |  |  |  |  |  |
Long-Term Debt And Equity Financings [Line Items] |  |  |  |  |  |  |  |  |
Debt Instrument, Face Amount |  |  |  |  |  |  |  | $ 95,000,000 |
Debt Instrument, Interest Rate, Stated Percentage |  |  | 2.96% |  |  | 2.96% |  |  |
Proceeds from Issuance of Debt | $ 95,000,000 |  |  |  |  |  |  |  |
Ameren Transmission Company of Illinois | Unsecured Debt | Senior Unsecured Notes, 3.43%, Due 2050 |  |  |  |  |  |  |  |  |
Long-Term Debt And Equity Financings [Line Items] |  |  |  |  |  |  |  |  |
Debt Instrument, Interest Rate, Stated Percentage |  |  | 3.43% |  |  | 3.43% |  |  |
Long-Term Debt, Maturity, Year One |  |  | $ 50,000,000 |  |  | $ 50,000,000 |  |  |

X
- Definition Accrued Proceeds from Issuance of Common Stock + References No definition available. + Details
Name: | aee_AccruedProceedsFromIssuanceOfCommonStock
Namespace Prefix: | aee_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Forward Contract Indexed to Issuer's Equity, Basis Spread + References No definition available. + Details
Name: | aee_ForwardContractIndexedToIssuersEquityBasisSpread
Namespace Prefix: | aee_
Data Type: | xbrli:pureItemType
Balance Type: | na
Period Type: | instant

X
- Definition Forward Sale Agreement, Compensation Received by Counterparty + References No definition available. + Details
Name: | aee_ForwardSaleAgreementCompensationReceivedByCounterparty
Namespace Prefix: | aee_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Forward Sale Agreement Equity Offering Shares + References No definition available. + Details
Name: | aee_ForwardSaleAgreementEquityOfferingShares
Namespace Prefix: | aee_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Forward Sale Agreement Gross Sales Price + References No definition available. + Details
Name: | aee_ForwardSaleAgreementGrossSalesPrice
Namespace Prefix: | aee_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Long-Term Debt And Equity Financings [Line Items] + References No definition available. + Details
Name: | aee_LongTermDebtAndEquityFinancingsLineItems
Namespace Prefix: | aee_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Maximum Value Of Shares To Be Issued Under ATM Program + References No definition available. + Details
Name: | aee_MaximumValueOfSharesToBeIssuedUnderATMProgram
Namespace Prefix: | aee_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Period End Net Cash Settlement Price + References No definition available. + Details
Name: | aee_PeriodEndNetCashSettlementPrice
Namespace Prefix: | aee_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Period End Net Share Settlement Price + References No definition available. + Details
Name: | aee_PeriodEndNetShareSettlementPrice
Namespace Prefix: | aee_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Face (par) amount of debt instrument at time of issuance. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 20 -Section 50 -Paragraph 1B -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495323-112611 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=124435984&loc=d3e28551-108399 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 55 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=124429444&loc=SL124452920-239629 Reference 5: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 20 -Section 55 -Paragraph 69C -URI http://asc.fasb.org/extlink&oid=123466577&loc=SL123495737-112612 Reference 6: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 20 -Section 55 -Paragraph 69B -URI http://asc.fasb.org/extlink&oid=123466577&loc=SL123495735-112612 + Details
Name: | us-gaap_DebtInstrumentFaceAmount
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Contractual interest rate for funds borrowed, under the debt agreement. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 20 -Section 50 -Paragraph 1B -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495323-112611 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22(a)(1)) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 + Details
Name: | us-gaap_DebtInstrumentInterestRateStatedPercentage
Namespace Prefix: | us-gaap_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition The per share price of the Company's stock at which the contract holder of the freestanding contract has the right to purchase or sell the Company's stock at a future date. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 40 -Section 50 -Paragraph 5 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=123477628&loc=d3e90205-114008 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 480 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (f)(1) -URI http://asc.fasb.org/extlink&oid=109262807&loc=d3e22047-110879 + Details
Name: | us-gaap_ForwardContractIndexedToIssuersEquityForwardRate
Namespace Prefix: | us-gaap_
Data Type: | dtr-types:perShareItemType
Balance Type: | na
Period Type: | duration

X
- Definition The number of issuer's shares to which the forward contract is indexed. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 40 -Section 50 -Paragraph 5 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=123477628&loc=d3e90205-114008 + Details
Name: | us-gaap_ForwardContractIndexedToIssuersEquityIndexedShares
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | instant

X
- Definition Amount that would be paid upon settlement of forward contract indexed to equity. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 40 -Section 50 -Paragraph 5 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=123477628&loc=d3e90205-114008 + Details
Name: | us-gaap_ForwardContractIndexedToIssuersEquitySettlementAlternativesCashAtFairValue
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Number of shares as a settlement alternative for each freestanding forward contract. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 40 -Section 50 -Paragraph 5 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=123477628&loc=d3e90205-114008 + Details
Name: | us-gaap_ForwardContractIndexedToIssuersEquitySettlementAlternativesSharesAtFairValue
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | instant

X
- Definition Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 20 -Section 50 -Paragraph 1E -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495348-112611 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 3 -Subparagraph (SX 210.12-04(a)) -URI http://asc.fasb.org/extlink&oid=120395691&loc=d3e24072-122690 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=123465755&loc=d3e1835-112601 + Details
Name: | us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition The cash inflow from the additional capital contribution to the entity. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 14 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3255-108585 + Details
Name: | us-gaap_ProceedsFromIssuanceOfCommonStock
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition The cash inflow from amounts received from issuance of long-term debt that is wholly or partially secured by collateral. Excludes proceeds from tax exempt secured debt. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 14 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3255-108585 + Details
Name: | us-gaap_ProceedsFromIssuanceOfSecuredDebt
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition The cash inflow from the issuance of long-term debt that is not secured by collateral. Excludes proceeds from tax exempt unsecured debt. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 14 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3255-108585 + Details
Name: | us-gaap_ProceedsFromIssuanceOfUnsecuredDebt
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Number of shares issued during the period from a dividend reinvestment plan (DRIP). A dividend reinvestment plan allows the shareholders to reinvest dividends paid to them by the entity on new issues of stock by the entity. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=123467817&loc=d3e21463-112644 + Details
Name: | us-gaap_StockIssuedDuringPeriodSharesDividendReinvestmentPlan
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- Definition Number of shares of stock issued attributable to transactions classified as other. + References No definition available. + Details
Name: | us-gaap_StockIssuedDuringPeriodSharesOther
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- Definition Value of shares of stock issued attributable to transactions classified as other. + References No definition available. + Details
Name: | us-gaap_StockIssuedDuringPeriodValueOther
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Details
Name: | srt_RangeAxis=srt_MinimumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RangeAxis=srt_MaximumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RangeAxis=srt_WeightedAverageMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_SubsidiarySaleOfStockAxis=aee_DividendReinvestmentAnd401KPlansMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ForwardContractIndexedToIssuersEquityTypeAxis=aee_ForwardSaleAgreementsOutstandingMember
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: | us-gaap_LongtermDebtTypeAxis=us-gaap_SecuredDebtMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=aee_SeniorSecuredNotes390Due2052Member
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: |

X
- Details
Name: | us-gaap_LongtermDebtTypeAxis=us-gaap_UnsecuredDebtMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=aee_SeniorSecuredNotes385Due2032Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=aee_SeniorSecuredNotes270Due2022Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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

X
- Details
Name: | us-gaap_DebtInstrumentAxis=aee_SeniorUnsecuredNotes296Due2052Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=aee_SeniorUnsecuredNotes3.43Due2050Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |