v3.25.4

Income Taxes (Summary of Loss and Credit Carryforwards) (Details) $ in Millions | Dec. 31, 2025 USD ($)
--- | ---
Operating Loss Carryforwards [Line Items] |
General business credits | $ 120
Total tax attributes | 139
Consumers Energy Company |
Operating Loss Carryforwards [Line Items] |
General business credits | 8
Total tax attributes | 18
Michigan State Tax Authority |
Operating Loss Carryforwards [Line Items] |
Local net operating loss carryforwards | 15
Michigan State Tax Authority | Consumers Energy Company |
Operating Loss Carryforwards [Line Items] |
Local net operating loss carryforwards | 10
Arkansas State Tax Authority |
Operating Loss Carryforwards [Line Items] |
Local net operating loss carryforwards | 2
Local Tax Authority |
Operating Loss Carryforwards [Line Items] |
Local net operating loss carryforwards | $ 2

X
- 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
Name: | cms_DeferredTaxAssetsNetOperatingLossAndTaxCreditCarryforwards
Namespace Prefix: | cms_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible state and local operating loss carryforwards. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 740 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482685/740-10-50-6 + Details
Name: | us-gaap_DeferredTaxAssetsOperatingLossCarryforwardsStateAndLocal
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible general business tax credit carryforwards. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 740 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482685/740-10-50-6 + Details
Name: | us-gaap_DeferredTaxAssetsTaxCreditCarryforwardsGeneralBusiness
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
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 Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 740 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482685/740-10-50-3 + Details
Name: | us-gaap_OperatingLossCarryforwardsLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

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

X
- Details
Name: | us-gaap_IncomeTaxAuthorityAxis=cms_MichiganStateTaxAuthorityMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_IncomeTaxAuthorityAxis=cms_ArkansasStateTaxAuthorityMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_IncomeTaxAuthorityAxis=cms_LocalJurisdictionMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |