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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- Definition

Current liabilities that represent obligations to make refunds to customers for fuel costs.

+ References

No definition available.

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- Definition

Unrecovered Power Supply Costs

+ References

No definition available.

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X

- Definition

Carrying amount as of the balance sheet date of capitalized fuel costs of a regulated entity that are expected to be recoverable through rate adjustments within one year or the normal operating cycle, if longer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 980
-SubTopic 340
-Name Accounting Standards Codification
-Section 25
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477711/980-340-25-1

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

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- Details

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