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Plant, Property, and Equipment (Schedule of Finance Leases and Other Financing Obligations) (Details) - Consumers Energy Company - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2020 | Dec. 31, 2019
Finance Leases and Other Financing Obligations, Rollforward [Roll Forward] |  |
Balance at beginning of period | $ 340 | $ 309
Additions | 0 | 26
Net retirements and other adjustments | (4) | 5
Balance at end of period | 336 | 340
Finance lease accumulated amortization | $ 254 | $ 239

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- Definition Finance Lease Asset, Net Retirements And Adjustments + References No definition available. + Details
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- Definition Finance Lease Assets, Additions + References No definition available. + Details
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- Definition Amount of accumulated amortization of right-of-use asset from finance lease. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=121609121&loc=SL77918686-209980 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 45 -Paragraph 4 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=121603541&loc=SL77918638-209977 + Details
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- Definition Amount, before accumulated amortization, of right-of-use asset from finance lease. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 45 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=121603541&loc=SL77918627-209977 + Details
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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. + References No definition available. + Details
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- Details
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