Financings and Capitalization (Narrative) (Details) - USD ($)	9 Months Ended
	Sep. 30, 2022	Dec. 31, 2021
Financing And Capitalization [Line Items]
Limitation on payment of stock dividends	$ 6,700,000,000
Dividends paid	593,000,000
Stock offering program maximum value	500,000,000
Net cash required to settle forward contracts	$ 1,000,000
Number of shares required to settle forward contracts (in shares)	13,504
Consumers Energy Company
Financing And Capitalization [Line Items]
Notes payable – related parties	$ 0	$ 392,000,000
Unrestricted retained earnings	1,900,000,000
Consumers Energy Company | Credit Agreement
Financing And Capitalization [Line Items]
Maximum borrowing capacity	500,000,000
Notes payable – related parties	$ 0
Consumers Energy Company | Credit Agreement | London Interbank Offered Rate (LIBOR)
Financing And Capitalization [Line Items]
Basis spread on variable rate	0.10%
Consumers Energy Company | Commercial Paper
Financing And Capitalization [Line Items]
Short-term debt authorized borrowings	$ 500,000,000
Short-term borrowings outstanding	$ 0