v3.25.4

Revenue (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Disaggregation of Revenue [Line Items]
Bad debt expense	$ 40	$ 33	$ 34
Unbilled receivables	659	584
Consumers Energy Company
Disaggregation of Revenue [Line Items]
Bad debt expense	40	33	$ 34
Unbilled receivables	$ 659	$ 584

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