XML 64 R44.htm IDEA: XBRL DOCUMENT
v3.23.2

Contingencies and Commitments (Summary of Guarantees) (Details) $ in Millions | 6 Months Ended
--- | ---
Jun. 30, 2023 USD ($)
Variable Interest Entity, Primary Beneficiary | Aviator Wind Class B Membership |
Guarantees And Other Contingencies [Line Items] |
Ownership percentage | 49.00%
Guarantees |
Guarantees And Other Contingencies [Line Items] |
Expiration Date | indefinite
Maximum Obligation | $ 30
Carrying Amount | $ 0
Guarantees | Consumers Energy Company |
Guarantees And Other Contingencies [Line Items] |
Expiration Date | indefinite
Maximum Obligation | $ 30
Carrying Amount | $ 0
Indemnification agreement from sale of membership interests in VIEs |
Guarantees And Other Contingencies [Line Items] |
Expiration Date | indefinite
Maximum Obligation | $ 308
Carrying Amount | $ 0
Indemnity obligations from stock and asset sale agreements |
Guarantees And Other Contingencies [Line Items] |
Expiration Date | indefinite
Maximum Obligation | $ 154
Carrying Amount | $ 2

X
- Definition Guarantees And Other Contingencies [Line Items] + References No definition available. + Details
Name: | cms_GuaranteesAndOtherContingenciesLineItems
Namespace Prefix: | cms_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition The current carrying amount of the liability for the freestanding or embedded guarantor's obligations under the guarantee or each group of similar guarantees. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 460 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 4 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482425/460-10-50-4 + Details
Name: | us-gaap_GuaranteeObligationsCurrentCarryingValue
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 460 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 4 -Subparagraph (b)(1) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482425/460-10-50-4 + Details
Name: | us-gaap_GuaranteeObligationsMaximumExposure
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Describe the approximate term of the guarantee or each group of similar guarantees. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 460 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 4 -Subparagraph (a)(1) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482425/460-10-50-4 + Details
Name: | us-gaap_GuaranteeObligationsTerm
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity. + References No definition available. + Details
Name: | us-gaap_MinorityInterestOwnershipPercentageByNoncontrollingOwners
Namespace Prefix: | us-gaap_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | instant

X
- Details
Name: | srt_ConsolidatedEntitiesAxis=us-gaap_VariableInterestEntityPrimaryBeneficiaryMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_OwnershipAxis=cms_AviatorWindClassBMembershipMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_GuaranteeObligationsByNatureAxis=us-gaap_GuaranteeTypeOtherMember
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: | us-gaap_LossContingenciesByNatureOfContingencyAxis=cms_IndemnificationAgreementFromSaleOfMembershipInterestsInVIEsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LossContingenciesByNatureOfContingencyAxis=us-gaap_IndemnificationGuaranteeMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |