XML 73 R58.htm IDEA: XBRL DOCUMENT
v3.19.1

Leases - Lessor Leases Narrative (Details) - USD ($) $ in Millions |  | 3 Months Ended |
--- | --- | --- | ---
Mar. 31, 2019 | Mar. 31, 2019 | Dec. 31, 2018
Power Sales Agreement |  |  |
Lessor, Lease, Description [Line Items] |  |  |
Leasing income |  | $ 48 |
Variable lease income |  | $ 34 |
Power Sales Agreement | Minimum |  |  |
Lessor, Lease, Description [Line Items] |  |  |
Operating leases remaining term | 7 years |  |
Power Sales Agreement | Maximum |  |  |
Lessor, Lease, Description [Line Items] |  |  |
Operating leases remaining term | 24 years |  |
Natural Gas Processing Plant | Consumers Energy Company |  |  |
Lessor, Lease, Description [Line Items] |  |  |
Direct financing lease term | 20 years | 20 years |
CMS Energy Subsidiary | Natural Gas Transportation Agreement | Consumers Energy Company |  |  |
Lessor, Lease, Description [Line Items] |  |  |
Direct financing lease term |  |  | 20 years

X
- Definition Lessee, Operating Lease, Remaining Lease Term + References No definition available. + Details
Name: | cms_LesseeOperatingLeaseRemainingLeaseTerm
Namespace Prefix: | cms_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Term of lessor's direct financing 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/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 30 -Section 50 -Paragraph 3 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=77888428&loc=SL77919359-209981 + Details
Name: | us-gaap_LessorDirectFinancingLeaseTermOfContract1
Namespace Prefix: | us-gaap_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | instant

X
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
Name: | us-gaap_LessorLeaseDescriptionLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of operating lease income from lease payments and variable lease payments paid and payable to lessor. Includes, but is not limited to, variable lease payments not included in measurement of lease receivable. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 30 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=77888428&loc=SL77919372-209981 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 30 -Section 45 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=77888421&loc=SL77919311-209978 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 270 -SubTopic 10 -Section 50 -Paragraph 6A -URI http://asc.fasb.org/extlink&oid=109225645&loc=SL77927221-108306 + Details
Name: | us-gaap_OperatingLeaseLeaseIncome
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount of operating lease income from variable lease payments paid and payable to lessor, excluding amount included in measurement of lease receivable. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 270 -SubTopic 10 -Section 50 -Paragraph 6A -URI http://asc.fasb.org/extlink&oid=109225645&loc=SL77927221-108306 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 30 -Section 50 -Paragraph 5 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=77888428&loc=SL77919372-209981 + Details
Name: | us-gaap_OperatingLeaseVariableLeaseIncome
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Details
Name: | us-gaap_FairValueByAssetClassAxis=cms_PowerSalesAgreementMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RangeAxis=srt_MinimumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RangeAxis=srt_MaximumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FairValueByAssetClassAxis=us-gaap_NaturalGasProcessingPlantMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | dei_LegalEntityAxis=cms_ConsumersEnergyCompanyMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_CounterpartyNameAxis=cms_CMSEnergySubsidiaryMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FairValueByAssetClassAxis=cms_NaturalGasTransportationAgreementMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |