Plant, Property, and Equipment (Summary of Composite Depreciation Rates for Properties) (Details) - Consumers Energy Company	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Electric utility property
Public Utility, Property, Plant and Equipment [Line Items]
Composite depreciation rate	3.80%	3.70%	3.90%
Gas utility property
Public Utility, Property, Plant and Equipment [Line Items]
Composite depreciation rate	2.80%	2.90%	2.90%
Other property
Public Utility, Property, Plant and Equipment [Line Items]
Composite depreciation rate	7.80%	8.90%	9.40%