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Leases (Narrative) (Details) - Consumers Energy Company [Member] | 12 Months Ended
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Dec. 31, 2015
Leases [Line Items] |
Finance Lease Term | 15 years
Coal-Carrying Railcars [Member] |
Leases [Line Items] |
Operating leases without extension provisions, remaining term | 10 years
Operating leases with extension provisions, remaining term | 11 years
Gas Transportation Pipeline into Karn [Member] |
Leases [Line Items] |
Capital Lease Term | 15 years
Capital Lease Remaining Term | 6 years
Gas Transportation Pipeline into Zeeland [Member] |
Leases [Line Items] |
Capital Lease Term | 5 years
Capital lease renewal term | 5 years
Capital Lease Remaining Term | 2 years
Minimum [Member] | Coal-Carrying Railcars [Member] |
Leases [Line Items] |
Operating leases, term | 1 year
Minimum [Member] | Long-term PPAs [Member] |
Leases [Line Items] |
Lease term | 1 year
Maximum [Member] | Coal-Carrying Railcars [Member] |
Leases [Line Items] |
Operating leases, term | 15 years
Maximum [Member] | Vehicle Fleet Operations [Member] |
Leases [Line Items] |
Capital Lease Term | 120 months
Maximum [Member] | Long-term PPAs [Member] |
Leases [Line Items] |
Lease term | 17 years

X
- Definition Remaining term of a capital lease contract before expiration. + References No definition available. + Details
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- Definition Capital lease renewal term + References No definition available. + Details
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- Definition Term of capital lease contract. + References No definition available. + Details
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- Definition Term of finance lease contract. + References No definition available. + Details
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- Definition Leases [Line Items] + References No definition available. + Details
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- Definition Time period remaining over which operating leases are expiring with extension provisions in the contracts. + References No definition available. + Details
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- Definition Time period remaining over which operating leases are expiring without extension provisions in the contracts. + References No definition available. + Details
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X
- Definition Term of the lessor's leasing arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
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- Details
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- Details
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- Details
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- Details
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- Details
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- Details
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- Details
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