Summary Of Significant Accounting Policies - Schedule of Other Assets and Other Liabilities (Details) - USD ($) $ in Millions |
Jun. 30, 2025 |
Dec. 31, 2024 |
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| Accounting Policies [Line Items] | ||
| Unbilled revenue | $ 467 | $ 346 |
| Other current assets | 258 | 162 |
| Regulatory Asset | 2,666 | 2,397 |
| Current maturities of long-term debt | 29 | 317 |
| Interest accrued | 230 | 196 |
| Long-term debt, net | 18,811 | 17,262 |
| Ameren Missouri Securitization Funding I, LLC | ||
| Accounting Policies [Line Items] | ||
| Unbilled revenue | 4 | 0 |
| Other current assets | 28 | 2 |
| Regulatory Asset | 454 | 465 |
| Current maturities of long-term debt | 29 | 17 |
| Interest accrued | 12 | 1 |
| Current regulatory liabilities | 8 | 0 |
| Long-term debt, net | $ 437 | $ 448 |
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- Definition [Line Items] for Accounting Policies [Table] No definition available.
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- Definition Carrying value as of the balance sheet date of [accrued] interest payable on all forms of debt, including trade payables, that has been incurred and is unpaid. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer). Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount, after deduction of unamortized premium (discount) and debt issuance cost, of long-term debt classified as current. Excludes lease obligation. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount, after deduction of unamortized premium (discount) and debt issuance cost, of long-term debt classified as noncurrent. Excludes lease obligation. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of current assets classified as other. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Carrying amount as of the balance sheet date of capitalized costs of regulated entities that are not expected to be recovered through revenue sources within one year or the normal operating cycle if longer. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition The amount for the individual regulatory current liability as itemized in a table of regulatory current liabilities as of the end of the period. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount received for services rendered and products shipped, but not yet billed, for non-contractual agreements due within one year or the normal operating cycle, if longer. No definition available.
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- Details
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