XML 72 R43.htm IDEA: XBRL DOCUMENT
v3.25.1

Short-Term Debt and Liquidity (Short-Term Debt Activity) (Details) - USD ($) $ in Millions | 3 Months Ended
--- | ---
Mar. 31, 2025 | Mar. 31, 2024
Short-term Debt [Line Items] |  |
Average daily amount outstanding | $ 1,293 | $ 471
Weighted-average interest rate | 4.60% | 5.57%
Short-term Debt, Maximum Amount Outstanding During Period | $ 1,603 | $ 869
Peak interest rate | 4.75% | 5.68%
Parent Company |  |
Short-term Debt [Line Items] |  |
Average daily amount outstanding | $ 898 | $ 0
Weighted-average interest rate | 4.61% | 0.00%
Short-term Debt, Maximum Amount Outstanding During Period | $ 1,139 | $ 0
Peak interest rate | 4.75% | 0.00%
Union Electric Company |  |
Short-term Debt [Line Items] |  |
Average daily amount outstanding | $ 313 | $ 135
Weighted-average interest rate | 4.59% | 5.53%
Short-term Debt, Maximum Amount Outstanding During Period | $ 630 | $ 444
Peak interest rate | 4.70% | 5.68%
Ameren Illinois Company |  |
Short-term Debt [Line Items] |  |
Average daily amount outstanding | $ 82 | $ 336
Weighted-average interest rate | 4.56% | 5.58%
Short-term Debt, Maximum Amount Outstanding During Period | $ 189 | $ 425
Peak interest rate | 4.69% | 5.68%

X
- Definition Peak Short Term Borrowings Interest Rate + References No definition available. + Details
Name: | aee_PeakShortTermBorrowingsInterestRate
Namespace Prefix: | aee_
Data Type: | dtr-types1:percentItemType
Balance Type: | na
Period Type: | duration

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_ShortTermDebtLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Weighted average interest rate of short-term debt outstanding calculated at point in time. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 470 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 7 -Publisher FASB -URI https://asc.fasb.org/1943274/2147481544/470-10-50-7 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 210 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(19)(b)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1 + Details
Name: | us-gaap_ShortTermDebtWeightedAverageInterestRate
Namespace Prefix: | us-gaap_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition For the form of debt having an initial term of less than one year or less than the normal operating cycle, if longer, average borrowings during the period. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name Regulation S-K (SK) -Number 229 -Section 1402 -Paragraph a -Publisher SEC Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name Regulation S-K (SK) -Number 229 -Section 1402 -Paragraph b -Subparagraph (1) -Publisher SEC Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 220 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.6-07(3)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479134/946-220-S99-1 + Details
Name: | us-gaap_ShorttermDebtAverageOutstandingAmount
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition For the form of debt having an initial term of less than one year or less than the normal operating cycle, if longer, the maximum amount borrowed at any time during the period. + References No definition available. + Details
Name: | us-gaap_ShorttermDebtMaximumAmountOutstandingDuringPeriod
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Details
Name: | srt_ConsolidatedEntitiesAxis=srt_ParentCompanyMember
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: |