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Leases - Lessee Leases Narrative (Details) | Mar. 31, 2019
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Lessee, Lease, Description [Line Items] |
Finance leases | 12 years
Operating leases | 14 years
Real Estate |
Lessee, Lease, Description [Line Items] |
Operating lease remaining term without extension provisions | 42 years
Minimum | Real Estate |
Lessee, Lease, Description [Line Items] |
Operating lease term | 3 years
Maximum | Real Estate |
Lessee, Lease, Description [Line Items] |
Operating lease term | 60 years
Consumers Energy Company |
Lessee, Lease, Description [Line Items] |
Finance leases | 12 years
Operating leases | 13 years
Consumers Energy Company | Railcars |
Lessee, Lease, Description [Line Items] |
Operating lease remaining term without extension provisions | 4 years
Consumers Energy Company | Real Estate |
Lessee, Lease, Description [Line Items] |
Operating lease remaining term without extension provisions | 42 years
Consumers Energy Company | Service Vehicles |
Lessee, Lease, Description [Line Items] |
Finance lease remaining term | 8 years
Consumers Energy Company | Minimum | Railcars |
Lessee, Lease, Description [Line Items] |
Operating lease term | 5 years
Consumers Energy Company | Minimum | Real Estate |
Lessee, Lease, Description [Line Items] |
Operating lease term | 3 years
Consumers Energy Company | Minimum | Service Vehicles |
Lessee, Lease, Description [Line Items] |
Finance lease term | 5 years
Consumers Energy Company | Minimum | PPAs |
Lessee, Lease, Description [Line Items] |
Operating and finance lease remaining term | 1 year
Consumers Energy Company | Maximum | Railcars |
Lessee, Lease, Description [Line Items] |
Operating lease term | 15 years
Consumers Energy Company | Maximum | Real Estate |
Lessee, Lease, Description [Line Items] |
Operating lease term | 60 years
Consumers Energy Company | Maximum | Service Vehicles |
Lessee, Lease, Description [Line Items] |
Finance lease term | 10 years
Consumers Energy Company | Maximum | PPAs |
Lessee, Lease, Description [Line Items] |
Operating and finance lease remaining term | 14 years
D.E. Karn Generating Complex | Consumers Energy Company | Gas Pipelines |
Lessee, Lease, Description [Line Items] |
Finance lease term | 15 years
Finance leases | 3 years
Zeeland | Consumers Energy Company | Gas Pipelines |
Lessee, Lease, Description [Line Items] |
Finance lease term | 5 years
Zeeland | Consumers Energy Company | Minimum | Gas Pipelines |
Lessee, Lease, Description [Line Items] |
Finance lease renewal term | 5 years
Zeeland | Consumers Energy Company | Maximum | Gas Pipelines |
Lessee, Lease, Description [Line Items] |
Finance lease renewal term | 10 years

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- Definition Weighted average remaining lease term for finance lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (g)(3) -URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918686-209980 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 55 -Paragraph 53 -URI http://asc.fasb.org/extlink&oid=77888399&loc=SL77918982-209971 + Details
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