Other Income and Other Expense (Components Of Other Income and Other Expense) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Other Income and Expenses [Line Items]
Interest income	$ 5	$ 3	$ 4
Interest income – related parties	0	0	7
Allowance for equity funds used during construction	6	8	6
Income from equity method investees	3	10	5
All other	5	9	6
Other income	19	30	28
Donations	(9)	(6)	(35)
Civic and political expenditures	(6)	(5)	(5)
Loss on reacquired and extinguished debt	0	0	(16)
All other	(12)	(7)	(6)
Total other expense	(27)	(18)	(62)
Consumers Energy Company
Other Income and Expenses [Line Items]
Interest income	2	2	3
Interest income – related parties	5	5	5
Allowance for equity funds used during construction	6	8	6
All other	4	8	5
Other income	17	23	19
Donations	(9)	(6)	(33)
Civic and political expenditures	(6)	(5)	(5)
All other	(10)	(7)	(5)
Total other expense	$ (25)	$ (18)	$ (43)