Regulatory Matters (Schedule Of Assets and Liabilities for PSCR And GCR Over/(Under) Recoveries) (Details) - USD ($) $ in Millions	Dec. 31, 2022	Dec. 31, 2021
Public Utilities, General Disclosures [Line Items]
Accrued rate refunds	$ 0	$ 12
Consumers Energy Company
Public Utilities, General Disclosures [Line Items]
Accounts receivable and accrued revenue	409	25
Accrued rate refunds	0	12
Consumers Energy Company \| PSCR underrecoveries
Public Utilities, General Disclosures [Line Items]
PSCR underrecoveries	401	0
Accrued rate refunds	0	12
Consumers Energy Company \| GCR underrecoveries
Public Utilities, General Disclosures [Line Items]
GCR underrecoveries	$ 8	$ 25

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

No definition available.

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Balance Type:	credit
Period Type:	instant

- Definition

Unrecovered Power Supply Costs

+ References

No definition available.

+ Details

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- 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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 980
-SubTopic 340
-Section 25
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=123417213&loc=d3e43603-110378

+ 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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 980
-SubTopic 340
-Section 50
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=6499975&loc=d3e44250-110382

+ Details

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- Details

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- Details

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- Details

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