Plant, Property, and Equipment (Schedule of Finance Leases and Other Financing Obligations) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Finance Leases and Other Financing Obligations, Rollforward [Roll Forward]
Balance at beginning of period	$ 332	$ 336
Additions	44	0
Net retirements and other adjustments	(206)	(4)
Balance at end of period	170	332
Consumers Energy Company
Finance Leases and Other Financing Obligations, Rollforward [Roll Forward]
Balance at beginning of period	332	336
Additions	20	0
Net retirements and other adjustments	(206)	(4)
Balance at end of period	146	332
Finance lease accumulated amortization	$ 88	$ 272