Accrual for Environmental Loss Contingencies, Inflation Rate

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Environmental Loss Contingency, Statement Of Financial Position, Extensible Enumeration, Not Disclosed Flag

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Loss Contingency, Additional Damages Awarded, Value

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Number Of Former Manufactured Gas Plants

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Regulatory Asset, Estimate Of Shared Costs

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Total costs accrued as of the balance sheet date for environmental loss contingencies.

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Rate applied to the undiscounted amount of environmental loss contingencies to arrive at the present value recorded as of the balance sheet date.

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Undiscounted amount of the accrual for environmental loss contingencies.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

Amount of damages awarded to the plaintiff in the legal matter.

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The value (monetary amount) of the award the plaintiff seeks in the legal matter.

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- Definition

Reflects the estimated amount of loss from the specified contingency as of the balance sheet date.

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Period of amortization for recovery of regulatory asset, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Carrying amount as of the balance sheet date of capitalized costs of regulated entities that are not expected to be recovered through revenue sources within one year or the normal operating cycle if longer.

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Contingencies and Commitments (Narrative) (Details) $ in Millions	1 Months Ended	6 Months Ended	12 Months Ended
	Dec. 31, 2025 USD ($)	Jun. 30, 2026 USD ($) facility	Dec. 31, 2022 USD ($)
Loss Contingencies [Line Items]
Environmental Loss Contingency, Statement Of Financial Position, Extensible Enumeration, Not Disclosed Flag		recorded liability
Regulatory assets	$ 3,355	$ 3,274
Consumers Energy Company
Loss Contingencies [Line Items]
Regulatory assets	3,355	3,274
Consumers Energy Company \| MGP sites
Loss Contingencies [Line Items]
Regulatory assets		78
Consumers Energy Company \| Ludington Plant Overhaul Contract Dispute
Loss Contingencies [Line Items]
Damages sought			$ 15
Damages awarded	383
Additional damages awarded	$ 11
Estimate of shared costs		350
Bay Harbor
Loss Contingencies [Line Items]
Accrual for environmental loss contingencies		$ 47
Discount rate (in percent)		4.34%
Accrual for environmental loss contingencies, inflation rate (in percent)		1.00%
Accrual for environmental loss contingencies, gross		$ 60
NREPA \| Electric Utility \| Consumers Energy Company
Loss Contingencies [Line Items]
Accrual for environmental loss contingencies		2
NREPA \| Maximum \| Electric Utility \| Consumers Energy Company
Loss Contingencies [Line Items]
Remediation and other response activity costs		3
CERCLA Liability \| Consumers Energy Company
Loss Contingencies [Line Items]
Accrual for environmental loss contingencies		21
CERCLA Liability \| Minimum \| Consumers Energy Company
Loss Contingencies [Line Items]
Remediation and other response activity costs		21
CERCLA Liability \| Maximum \| Consumers Energy Company
Loss Contingencies [Line Items]
Remediation and other response activity costs		57
MGP sites \| Consumers Energy Company
Loss Contingencies [Line Items]
Accrual for environmental loss contingencies		$ 58
Number of former MGPs \| facility		23
Regulatory asset collection period (in years)		10 years