Plant, Property, and Equipment (Schedule of Finance Leases and Other Financing Obligations) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024
Finance Leases and Other Financing Obligations, Rollforward [Roll Forward]
Balance at beginning of period	$ 176	$ 136
Additions	53	55
Net retirements and other adjustments	(36)	(15)
Balance at end of period	193	176
Consumers Energy Company
Finance Leases and Other Financing Obligations, Rollforward [Roll Forward]
Balance at beginning of period	131	112
Additions	22	34
Net retirements and other adjustments	(15)	(15)
Balance at end of period	$ 138	$ 131