Plant, Property, and Equipment (Schedule of Finite-Lived Intangible Assets by Major Class Table) (Details) - Consumers Energy Company - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Public Utility, Property, Plant and Equipment [Line Items]
Gross cost	$ 1,114	$ 1,102
Accumulated Amortization	686	684
Plant additions	2,300	2,400
Plant retirements	290	361
Software development
Public Utility, Property, Plant and Equipment [Line Items]
Gross cost	846	840
Accumulated Amortization	593	592
Leasehold improvements
Public Utility, Property, Plant and Equipment [Line Items]
Gross cost	9	9
Accumulated Amortization	6	6
Intangible plant
Public Utility, Property, Plant and Equipment [Line Items]
Plant additions	116	88
Plant retirements	104	91
Rights of way
Public Utility, Property, Plant and Equipment [Line Items]
Gross cost	218	211
Accumulated Amortization	61	60
Franchises and consents
Public Utility, Property, Plant and Equipment [Line Items]
Gross cost	16	16
Accumulated Amortization	10	10
Other intangible assets
Public Utility, Property, Plant and Equipment [Line Items]
Gross cost	25	26
Accumulated Amortization	$ 16	$ 16
Minimum | Software development
Public Utility, Property, Plant and Equipment [Line Items]
Amortization Life in Years	3 years
Minimum | Rights of way
Public Utility, Property, Plant and Equipment [Line Items]
Amortization Life in Years	50 years
Minimum | Franchises and consents
Public Utility, Property, Plant and Equipment [Line Items]
Amortization Life in Years	5 years
Maximum | Software development
Public Utility, Property, Plant and Equipment [Line Items]
Amortization Life in Years	15 years
Maximum | Rights of way
Public Utility, Property, Plant and Equipment [Line Items]
Amortization Life in Years	85 years
Maximum | Franchises and consents
Public Utility, Property, Plant and Equipment [Line Items]
Amortization Life in Years	50 years