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Regulatory Matters (Schedule Of Assets and Liabilities for PSCR And GCR Over/(Under) Recoveries) (Details) - USD ($) $ in Millions | Dec. 31, 2021 | Dec. 31, 2020
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Public Utilities, General Disclosures [Line Items] |  |
Accrued rate refunds | $ 12 | $ 20
Consumers Energy Company |  |
Public Utilities, General Disclosures [Line Items] |  |
Accounts receivable and accrued revenue | 25 | 0
Accrued rate refunds | 12 | 20
Consumers Energy Company | PSCR overrecoveries/underrecoveries |  |
Public Utilities, General Disclosures [Line Items] |  |
Accrued rate refunds | 12 | 5
Consumers Energy Company | GCR overrecoveries/underrecoveries |  |
Public Utilities, General Disclosures [Line Items] |  |
Accounts receivable and accrued revenue | 25 | 0
Accrued rate refunds | $ 0 | $ 15

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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 http://asc.fasb.org/extlink&oid=6499975&loc=d3e44250-110382 + Details
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