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Income Taxes (Schedule Of Deferred Tax Assets And Liabilities Resulting From Temporary Differences) (Details) - USD ($) $ in Millions | Dec. 31, 2025 | Dec. 31, 2024
--- | --- | ---
Income Taxes [Line Items] |  |
Plant-related | $ 5,312 | $ 4,940
Regulatory assets and liabilities, net | (325) | (385)
Deferred employee benefit costs - asset | 71 | 27
Tax carryforwards | (343) | (503)
Other - liabilities | 203 | 162
Total net accumulated deferred income tax liabilities (assets) | 4,918 | 4,241
Accumulated deferred investment tax credits | 263 | 233
Accumulated deferred income taxes and investment tax credits | 5,181 | 4,474
Ameren Missouri |  |
Income Taxes [Line Items] |  |
Plant-related | 2,652 | 2,429
Regulatory assets and liabilities, net | (179) | (193)
Deferred Tax Liabilities, Deferred Expense | (2) | (25)
Tax carryforwards | (190) | (355)
Other - liabilities | 161 | 131
Total net accumulated deferred income tax liabilities (assets) | 2,442 | 1,987
Accumulated deferred investment tax credits | 260 | 230
Accumulated deferred income taxes and investment tax credits | 2,702 | 2,217
Ameren Illinois |  |
Income Taxes [Line Items] |  |
Plant-related | 2,416 | 2,250
Regulatory assets and liabilities, net | (130) | (170)
Deferred employee benefit costs - asset | 89 | 77
Tax carryforwards | (45) | (45)
Other - liabilities | 21 | 28
Total net accumulated deferred income tax liabilities (assets) | 2,351 | 2,140
Accumulated deferred investment tax credits | 3 | 3
Accumulated deferred income taxes and investment tax credits | 2,354 | 2,143
Other |  |
Income Taxes [Line Items] |  |
Plant-related | 244 | 261
Regulatory assets and liabilities, net | (16) | (22)
Deferred Tax Liabilities, Deferred Expense | (16) | (25)
Tax carryforwards | (108) | (103)
Other - liabilities | 21 | 3
Total net accumulated deferred income tax liabilities (assets) | 125 | 114
Accumulated deferred investment tax credits | 0 | 0
Accumulated deferred income taxes and investment tax credits | $ 125 | $ 114

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- Definition The noncurrent portion of the reserve for accumulated deferred investment tax credits as of the balance sheet date. This is the remaining investment credit, which will reduce the cost of services collected from ratepayers by a ratable portion over the investment's regulatory life. + References Reference 1: 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(26)(b)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 740 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 27 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482525/740-10-45-27 + Details
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