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Other Income and Other Expense (Details) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Other Income and Expenses [Line Items] |  |  |
Donations | $ (35) | $ (3) | $ (13)
Civic and political expenditures | (5) | (6) | (6)
Loss on reacquired and extinguished debt | (16) | 0 | (16)
All other | (6) | (4) | (13)
Total other expense | (62) | (13) | (48)
Consumers Energy Company |  |  |
Other Income and Expenses [Line Items] |  |  |
Donations | (33) | (3) | (13)
Civic and political expenditures | (5) | (6) | (6)
All other | (5) | (4) | (11)
Total other expense | $ (43) | $ (13) | $ (30)

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- Definition The amount of expenses incurred related to civic and political activities during the period + References No definition available. + Details
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- Definition The amount of donations made to charitable organizations during the period + References No definition available. + Details
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- Definition The amount of other miscellaneous expense which are not identified separately as a component in Other expense table. + References No definition available. + Details
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- Definition Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 50 -Section 40 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=117329964&loc=d3e12355-112629 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 50 -Section 40 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=117329964&loc=d3e12317-112629 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3602-108585 + Details
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- Definition Amount of expense related to nonoperating activities, classified as other. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.9) -URI http://asc.fasb.org/extlink&oid=120395209&loc=SL114868664-224227 + Details
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