v3.25.4

Other Income and Other Expense (Summary of Components of Other Income and Other Expense) (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2025 | Dec. 31, 2024 | Dec. 31, 2023
Other Income and Expenses [Line Items] |  |  |
Allowance for equity funds used during construction | $ 23 | $ 29 | $ 7
Income from equity method investees | 5 | 7 | 7
All other | 13 | 11 | 13
Other income | 151 | 207 | 195
Donations | (10) | (18) | (1)
Civic and political expenditures | (7) | (5) | (5)
All other | (10) | (9) | (7)
Total other expense | (27) | (32) | (13)
First mortgage bonds |  |  |
Other Income and Expenses [Line Items] |  |  |
Gain on extinguishment of debt | 72 | 110 | 131
Nonrelated Party |  |  |
Other Income and Expenses [Line Items] |  |  |
Interest income | 37 | 50 | 37
Related Party |  |  |
Other Income and Expenses [Line Items] |  |  |
Interest income | 1 | 0 | 0
Consumers Energy Company |  |  |
Other Income and Expenses [Line Items] |  |  |
Allowance for equity funds used during construction | 23 | 29 | 7
All other | 6 | 9 | 12
Other income | 55 | 85 | 49
Donations | (10) | (18) | (1)
Civic and political expenditures | (5) | (5) | (5)
All other | (7) | (7) | (6)
Total other expense | (22) | (30) | (12)
Consumers Energy Company | Nonrelated Party |  |  |
Other Income and Expenses [Line Items] |  |  |
Interest income | 22 | 42 | 25
Consumers Energy Company | Related Party |  |  |
Other Income and Expenses [Line Items] |  |  |
Interest income | $ 4 | $ 5 | $ 5

X
- Definition The amount of expenses incurred related to civic and political activities during the period + References No definition available. + Details
Name: | cms_CivicAndPoliticalExpenditures
Namespace Prefix: | cms_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition The amount of donations made to charitable organizations during the period + References No definition available. + Details
Name: | cms_Donations
Namespace Prefix: | cms_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition [Line Items] for Other Income and Expenses [Table] + References No definition available. + Details
Name: | cms_OtherIncomeandExpensesLineItems
Namespace Prefix: | cms_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Other Nonoperating Income, Other + References No definition available. + Details
Name: | cms_OtherNonoperatingIncomeOther
Namespace Prefix: | cms_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition The amount of other miscellaneous expense which are not identified separately as a component in Other expense table. + References No definition available. + Details
Name: | cms_OtherOtherNonoperatingExpense
Namespace Prefix: | cms_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section 45 -Paragraph 28 -Subparagraph (b) -SubTopic 10 -Topic 230 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482740/230-10-45-28 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 470 -SubTopic 50 -Section 40 -Paragraph 2 -Publisher FASB -URI https://asc.fasb.org/1943274/2147481303/470-50-40-2 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 470 -SubTopic 50 -Section 40 -Paragraph 4 -Publisher FASB -URI https://asc.fasb.org/1943274/2147481303/470-50-40-4 + Details
Name: | us-gaap_GainsLossesOnExtinguishmentOfDebt
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount of income (loss) for proportionate share of equity method investee's income (loss). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section 45 -Paragraph 28 -Subparagraph (b) -SubTopic 10 -Topic 230 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482740/230-10-45-28 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 270 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (i) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482964/270-10-50-1 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 280 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 32 -Subparagraph (ee) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482810/280-10-50-32 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 944 -SubTopic 220 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04(10)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147477250/944-220-S99-1 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Topic 323 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147481664/323-10-45-1 Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Topic 280 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 22 -Subparagraph (g) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482810/280-10-50-22 Reference 7: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 220 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03(12)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147483621/220-10-S99-2 Reference 8: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 942 -SubTopic 220 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04(13)(f)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478524/942-220-S99-1 + Details
Name: | us-gaap_IncomeLossFromEquityMethodInvestments
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount of interest income earned from interest bearing assets classified as other. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 220 -SubTopic 40 -Name Accounting Standards Codification -Section 55 -Paragraph 21 -Publisher FASB -URI https://asc.fasb.org/1943274/2147476153/220-40-55-21 + Details
Name: | us-gaap_InterestIncomeOther
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount of expense related to nonoperating activities, classified as other. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 220 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03(9)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147483621/220-10-S99-2 + Details
Name: | us-gaap_OtherNonoperatingExpense
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of income related to nonoperating activities, classified as other. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 220 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03(7)(d)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147483621/220-10-S99-2 + Details
Name: | us-gaap_OtherNonoperatingIncome
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Total increase in earnings in the period representing the cost of equity (based on assumed rate of return) and/or borrowed funds (based on interest rate) used to finance construction of regulated assets, which is expected to be recovered through rate adjustments. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section 45 -Paragraph 28 -Subparagraph (b) -SubTopic 10 -Topic 230 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482740/230-10-45-28 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 980 -SubTopic 360 -Section 25 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147477468/980-360-25-1 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 980 -SubTopic 340 -Section 50 -Paragraph 3 -Publisher FASB -URI https://asc.fasb.org/1943274/2147478742/980-340-50-3 + Details
Name: | us-gaap_PublicUtilitiesAllowanceForFundsUsedDuringConstructionAdditions
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Details
Name: | us-gaap_LongtermDebtTypeAxis=cms_FirstMortgageBondsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=us-gaap_NonrelatedPartyMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=us-gaap_RelatedPartyMember
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: |