Earnings Per Share - CMS Energy (Narrative) (Details)	Mar. 31, 2024 USD ($)
CMS Energy \| 3.375% Convertible Senior Notes Due 2028 \| Convertible debt
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Principal (In Millions)

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

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