Earnings Per Share - CMS Energy (Basic And Diluted EPS Computations) (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Income available to common stockholders
Income from continuing operations	$ 182	$ 189	$ 445	$ 383
Loss attributable to noncontrolling interests	(16)	(8)	(40)	(18)
Preferred stock dividends	3	3	5	5
Income from continuing operations available to common stockholders – basic and diluted	$ 195	$ 194	$ 480	$ 396
Average common shares outstanding
Weighted average shares - basic (in shares)	297.9	290.9	297.2	290.8
Dilutive nonvested stock awards (in shares)	0.6	0.4	0.7	0.4
Weighted average shares - diluted (in shares)	298.5	291.3	297.9	291.2
Income from continuing operations per average common share available to common stockholders
Basic (in dollars per share)	$ 0.65	$ 0.67	$ 1.61	$ 1.36
Diluted (in dollars per share)	$ 0.65	$ 0.67	$ 1.61	$ 1.36