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Income Taxes (Loss And Credit Carryforwards) (Details) $ in Millions | Dec. 31, 2020 USD ($)
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Operating Loss Carryforwards [Line Items] |
General business credits | $ 245
Total tax attributes | 483
Consumers Energy Company |
Operating Loss Carryforwards [Line Items] |
General business credits | 49
Total tax attributes | 216
Federal Tax Authority |
Operating Loss Carryforwards [Line Items] |
Net operating loss carryforwards | 747
Federal net operating loss carryforwards | 157
Federal Tax Authority | Consumers Energy Company |
Operating Loss Carryforwards [Line Items] |
Net operating loss carryforwards | 505
Federal net operating loss carryforwards | 106
State Tax Authority |
Operating Loss Carryforwards [Line Items] |
Net operating loss carryforwards | 1,241
Local net operating loss carryforwards | 78
State Tax Authority | Consumers Energy Company |
Operating Loss Carryforwards [Line Items] |
Net operating loss carryforwards | 1,026
Local net operating loss carryforwards | 61
Local Tax Authority |
Operating Loss Carryforwards [Line Items] |
Net operating loss carryforwards | 346
Local net operating loss carryforwards | 3
General business credits |
Operating Loss Carryforwards [Line Items] |
Tax credits | 245
General business credits | Consumers Energy Company |
Operating Loss Carryforwards [Line Items] |
Tax credits | $ 49

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- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards and deductible tax credit carryforwards including, but not limited to, research, foreign, general business, alternative minimum tax, and other deductible tax credit carryforwards. + References No definition available. + Details
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