Plant, Property, and Equipment (Summary of Composite Depreciation Rates for Properties) (Details) - Consumers Energy Company	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Electric utility property
Public Utility, Property, Plant and Equipment [Line Items]
Composite depreciation rate	3.60%	3.60%	3.80%
Gas utility property
Public Utility, Property, Plant and Equipment [Line Items]
Composite depreciation rate	2.50%	2.50%	2.80%
Other property
Public Utility, Property, Plant and Equipment [Line Items]
Composite depreciation rate	7.00%	7.10%	7.80%