Other Income and Other Expense (Summary of Components of Other Income and Other Expense) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Other Income and Expenses [Line Items]
Gain on extinguishment of debt		$ 0	$ 0
Allowance for equity funds used during construction	$ 7	6	8
Income from equity method investees	7	3	10
All other	13	5	9
Other income	195	19	30
Donations	(1)	(9)	(6)
Civic and political expenditures	(5)	(6)	(5)
All other	(7)	(12)	(7)
Total other expense	(13)	(27)	(18)
Nonrelated Party
Other Income and Expenses [Line Items]
Interest income	37	5	3
Consumers Energy Company
Other Income and Expenses [Line Items]
Allowance for equity funds used during construction	7	6	8
All other	12	4	8
Other income	49	17	23
Donations	(1)	(9)	(6)
Civic and political expenditures	(5)	(6)	(5)
All other	(6)	(10)	(7)
Total other expense	(12)	(25)	(18)
Consumers Energy Company | Nonrelated Party
Other Income and Expenses [Line Items]
Interest income	25	2	2
Consumers Energy Company | Related Party
Other Income and Expenses [Line Items]
Interest income	$ 5	$ 5	$ 5