v3.25.4

Regulatory Matters (Schedule of Regulatory Assets and Liabilities) (Details) - USD ($) $ in Millions | Dec. 31, 2025 | Dec. 31, 2024
--- | --- | ---
Public Utilities, General Disclosures [Line Items] |  |
Total current regulatory assets | $ 104 | $ 229
Total non-current regulatory assets | 3,355 | 3,569
Total current regulatory liabilities | 85 | 111
Total non-current regulatory liabilities | 4,091 | 4,067
Consumers Energy Company |  |
Public Utilities, General Disclosures [Line Items] |  |
Total current regulatory assets | 104 | 229
Total non-current regulatory assets | 3,355 | 3,569
Total regulatory assets | 3,459 | 3,798
Total current regulatory liabilities | 85 | 111
Total non-current regulatory liabilities | 4,091 | 4,067
Total regulatory liabilities | 4,176 | 4,178
Income taxes, net | Consumers Energy Company |  |
Public Utilities, General Disclosures [Line Items] |  |
Total current regulatory liabilities | 47 | 53
Total non-current regulatory liabilities | 1,118 | 1,163
ASP gain | Consumers Energy Company |  |
Public Utilities, General Disclosures [Line Items] |  |
Total current regulatory liabilities | 28 | 47
Total non-current regulatory liabilities | 19 | 46
Other | Consumers Energy Company |  |
Public Utilities, General Disclosures [Line Items] |  |
Total current regulatory liabilities | 10 | 11
Total non-current regulatory liabilities | 40 | 24
Cost of removal | Consumers Energy Company |  |
Public Utilities, General Disclosures [Line Items] |  |
Total non-current regulatory liabilities | 2,727 | 2,665
Energy waste reduction plan | Consumers Energy Company |  |
Public Utilities, General Disclosures [Line Items] |  |
Total non-current regulatory liabilities | 68 | 41
Green Giving Program | Consumers Energy Company |  |
Public Utilities, General Disclosures [Line Items] |  |
Total non-current regulatory liabilities | 41 | 0
Postretirement benefits expense deferral mechanism | Consumers Energy Company |  |
Public Utilities, General Disclosures [Line Items] |  |
Total non-current regulatory liabilities | 40 | 37
Renewable energy grant | Consumers Energy Company |  |
Public Utilities, General Disclosures [Line Items] |  |
Total non-current regulatory liabilities | 38 | 40
Renewable Energy Plan | Consumers Energy Company |  |
Public Utilities, General Disclosures [Line Items] |  |
Total non-current regulatory liabilities | 0 | 51
Energy waste reduction plan incentive | Consumers Energy Company |  |
Public Utilities, General Disclosures [Line Items] |  |
Total current regulatory assets | 66 | 60
Total non-current regulatory assets | 64 | 64
Retention incentive program | Consumers Energy Company |  |
Public Utilities, General Disclosures [Line Items] |  |
Total current regulatory assets | 10 | 18
Total non-current regulatory assets | 6 | 12
2022 PSCR underrecovery | Consumers Energy Company |  |
Public Utilities, General Disclosures [Line Items] |  |
Total current regulatory assets | 0 | 126
Other | Consumers Energy Company |  |
Public Utilities, General Disclosures [Line Items] |  |
Total current regulatory assets | 28 | 25
Total non-current regulatory assets | 54 | 25
Costs of coal-fueled electric generating units to be retired | Consumers Energy Company |  |
Public Utilities, General Disclosures [Line Items] |  |
Total non-current regulatory assets | 1,179 | 1,266
Postretirement benefits | Consumers Energy Company |  |
Public Utilities, General Disclosures [Line Items] |  |
Total non-current regulatory assets | 589 | 747
Securitized costs | Consumers Energy Company |  |
Public Utilities, General Disclosures [Line Items] |  |
Total non-current regulatory assets | 549 | 666
ARO | Consumers Energy Company |  |
Public Utilities, General Disclosures [Line Items] |  |
Total non-current regulatory assets | 379 | 366
Decommissioning costs | Consumers Energy Company |  |
Public Utilities, General Disclosures [Line Items] |  |
Total non-current regulatory assets | 197 | 158
Unamortized loss on reacquired debt | Consumers Energy Company |  |
Public Utilities, General Disclosures [Line Items] |  |
Total non-current regulatory assets | 89 | 92
MGP sites | Consumers Energy Company |  |
Public Utilities, General Disclosures [Line Items] |  |
Total non-current regulatory assets | 82 | 90
Ludington overhaul contract dispute | Consumers Energy Company |  |
Public Utilities, General Disclosures [Line Items] |  |
Total non-current regulatory assets | 60 | 31
Service restoration cost deferral | Consumers Energy Company |  |
Public Utilities, General Disclosures [Line Items] |  |
Total non-current regulatory assets | 52 | 0
Energy waste reduction plan | Consumers Energy Company |  |
Public Utilities, General Disclosures [Line Items] |  |
Total non-current regulatory assets | 26 | 31
Postretirement benefits expense deferral mechanism | Consumers Energy Company |  |
Public Utilities, General Disclosures [Line Items] |  |
Total non-current regulatory assets | 22 | 21
Renewable Energy Plan | Consumers Energy Company |  |
Public Utilities, General Disclosures [Line Items] |  |
Total non-current regulatory assets | $ 7 | $ 0

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- Definition Carrying amount as of the balance sheet date of capitalized costs of regulated entities that are expected to be recovered through revenue sources within one year or the normal operating cycle, if longer. Such costs are capitalized if they meet both of the following criteria: a. It is probable that future revenue in an amount at least equal to the capitalized cost will result from inclusion of that cost in allowable costs for rate-making purposes. b. Based on available evidence, the future revenue will be provided to permit recovery of the previously incurred cost rather than to provide for expected levels of similar future costs. If the revenue will be provided through an automatic rate-adjustment clause, this criterion requires that the regulator's intent clearly be to permit recovery of the previously incurred cost. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 980 -SubTopic 340 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147478742/980-340-50-1 + Details
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