Percentage points added to the reference rate to compute the variable rate on the debt instrument.

No definition available.

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Face (par) amount of debt instrument at time of issuance.

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Contractual interest rate for funds borrowed, under the debt agreement.

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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.

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Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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Amount of cash outflow for short-term and long-term debt. Excludes payment of lease obligation.

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Financings and Capitalization (Major Long-Term Debt Issuances and Retirements) (Details) - USD ($) $ in Millions		3 Months Ended	6 Months Ended
	Jun. 01, 2035	Mar. 31, 2025	Jun. 30, 2026
Debt Instrument [Line Items]
Principal Debt Issuances (In Millions)		$ 1,200
Principal Debt Retirements (In Millions)		600
CMS Energy
Debt Instrument [Line Items]
Principal Debt Issuances (In Millions)		1,110
Principal Debt Retirements (In Millions)		600
CMS Energy \| Junior subordinated notes \| 6.500% Junior Subordinated Notes Due June 2055
Debt Instrument [Line Items]
Principal Debt Issuances (In Millions)		$ 1,000
Interest Rate (%)		6.50%
CMS Energy \| Junior subordinated notes \| 6.500% Junior Subordinated Notes Due June 2055 \| Forecast
Debt Instrument [Line Items]
Basis spread on variable rate	1.961%
CMS Energy \| Term loan facility \| Term Loan Facility Due December 2025
Debt Instrument [Line Items]
Principal Debt Issuances (In Millions)		$ 110
Principal Debt Retirements (In Millions)		200
CMS Energy \| Term loan facility \| Term Loan Facility Due September 2025
Debt Instrument [Line Items]
Principal Debt Retirements (In Millions)		400
NorthStar Clean Energy, Including Subsidiaries
Debt Instrument [Line Items]
Principal Debt Issuances (In Millions)		90
NorthStar Clean Energy, Including Subsidiaries \| Construction financing agreement \| Construction Financing Agreement
Debt Instrument [Line Items]
Principal Debt Issuances (In Millions)		$ 90
NorthStar Clean Energy, Including Subsidiaries \| Construction financing agreement \| Construction Financing Agreement \| Forecast
Debt Instrument [Line Items]
Debt Instrument, Term			5 years