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Income Taxes (Schedule Of Deferred Tax Assets And Liabilities Resulting From Temporary Differences) (Details) - USD ($) $ in Millions | Dec. 31, 2023 | Dec. 31, 2022
--- | --- | ---
Income Taxes [Line Items] |  |
Plant-related | $ 4,646 | $ 4,416
Regulatory assets and liabilities, net | (413) | (449)
Deferred employee benefit costs - asset | (26) | (70)
Tax carryforwards | (218) | (228)
Other - liabilities | 161 | 110
Total net accumulated deferred income tax liabilities (assets) | 4,150 | 3,779
Accumulated deferred investment tax credits | 26 | 25
Accumulated deferred income taxes and investment tax credits | 4,176 | 3,804
Ameren Missouri |  |
Income Taxes [Line Items] |  |
Plant-related | 2,370 | 2,297
Regulatory assets and liabilities, net | (206) | (233)
Deferred employee benefit costs - asset | (48) | (55)
Tax carryforwards | (124) | (122)
Other - liabilities | 104 | 70
Total net accumulated deferred income tax liabilities (assets) | 2,096 | 1,957
Accumulated deferred investment tax credits | 26 | 25
Accumulated deferred income taxes and investment tax credits | 2,122 | 1,982
Ameren Illinois |  |
Income Taxes [Line Items] |  |
Plant-related | 2,030 | 1,880
Regulatory assets and liabilities, net | (184) | (193)
Deferred employee benefit costs - liability | 55 | 28
Tax carryforwards | (33) | (34)
Other - liabilities | 38 | 18
Total net accumulated deferred income tax liabilities (assets) | 1,906 | 1,699
Accumulated deferred investment tax credits | 0 | 0
Accumulated deferred income taxes and investment tax credits | 1,906 | 1,699
Other |  |
Income Taxes [Line Items] |  |
Plant-related | 246 | 239
Regulatory assets and liabilities, net | (23) | (23)
Deferred employee benefit costs - asset | (33) | (43)
Tax carryforwards | (61) | (72)
Other - liabilities | 19 | 22
Total net accumulated deferred income tax liabilities (assets) | 148 | 123
Accumulated deferred investment tax credits | 0 | 0
Accumulated deferred income taxes and investment tax credits | $ 148 | $ 123

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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://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 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.26(b)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1 + Details
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