Regulatory Matters (Schedule of Assets and Liabilities for PSCR and GCR Over/(Under) Recoveries) (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Public Utilities, General Disclosures [Line Items]
Accrued rate refunds	$ 54	$ 0
Consumers Energy Company
Public Utilities, General Disclosures [Line Items]
Accounts receivable and accrued revenue	0	409
Accrued rate refunds	54	0
Consumers Energy Company \| PSCR underrecoveries
Public Utilities, General Disclosures [Line Items]
PSCR underrecoveries	0	401
Accrued rate refunds	10	0
Consumers Energy Company \| GCR underrecoveries
Public Utilities, General Disclosures [Line Items]
GCR underrecoveries	0	8
Accrued rate refunds	$ 44	$ 0

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

No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Unrecovered Power Supply Costs

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- 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//1943274/2147482000/980-340-25-1

+ Details

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Balance Type:	debit
Period Type:	instant

- 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

No definition available.

+ Details

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- Definition

Discloses the amount of unrecovered costs for purchased gas.

+ 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//1943274/2147481878/980-340-50-1

+ Details

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- Details

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- Details

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- Details

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