v3.25.4

Income Taxes (Narrative) (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2026 | Dec. 31, 2025 | Dec. 31, 2024 | Dec. 31, 2023
Income Tax Benefits [Line Items] |  |  |  |
Deferred income taxes and investment tax credits |  | $ 202 | $ 142 | $ 157
Local Tax Authority |  |  |  |
Income Tax Benefits [Line Items] |  |  |  |
Valuation allowance - loss carryforward |  | 2 |  |
Consumers Energy Company |  |  |  |
Income Tax Benefits [Line Items] |  |  |  |
Deferred income taxes and investment tax credits |  | 48 | $ 115 | $ 156
2024 Renewable Energy Tax Credits |  |  |  |
Income Tax Benefits [Line Items] |  |  |  |
Deferred income taxes and investment tax credits |  | 13 |  |
2025 Renewable Energy Tax Credits | Forecast |  |  |  |
Income Tax Benefits [Line Items] |  |  |  |
Deferred income taxes and investment tax credits | $ 32 |  |  |
2025 Renewable Energy Tax Credits | Consumers Energy Company |  |  |  |
Income Tax Benefits [Line Items] |  |  |  |
Deferred income taxes and investment tax credits |  | $ 36 |  |
2025 Renewable Energy Tax Credits | Consumers Energy Company | Forecast |  |  |  |
Income Tax Benefits [Line Items] |  |  |  |
Deferred income taxes and investment tax credits | $ 10 |  |  |

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- Definition Amount of deferred income tax expense (benefit) and income tax credits. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 230 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 28 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482740/230-10-45-28 + Details
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- Definition The portion of the valuation allowance pertaining to the deferred tax asset representing potential future taxable deductions from net operating loss carryforwards for which it is more likely than not that a tax benefit will not be realized. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 740 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482685/740-10-50-2 + Details
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