v3.25.4

Regulatory Matters (Schedule of Liabilities for PSCR and GCR Overrecoveries) (Details) - USD ($) $ in Millions | Dec. 31, 2025 | Dec. 31, 2024 | Dec. 31, 2022
--- | --- | --- | ---
Public Utilities, General Disclosures [Line Items] |  |  |
Accrued rate refunds | $ 28 | $ 38 |
Consumers Energy Company |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |
Accounts receivable and accrued revenue | 38 | 0 |
Accrued rate refunds | 28 | 38 |
Consumers Energy Company | PSCR underrecoveries |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |
PSCR underrecoveries | 38 | 0 | $ 401
Accrued rate refunds | 0 | 13 |
Consumers Energy Company | GCR underrecoveries |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |
Accrued rate refunds | $ 28 | $ 25 |

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