The amount of dividends that may be paid or declared in any calendar year, limited by statutory restriction.

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Financing And Capitalization [Line Items]

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- Definition

Maximum borrowing capacity under the commercial paper program without consideration of any current restrictions on the amount that could be issued or the amounts currently outstanding under the program.

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No definition available.

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The maximum value of new stock which can be issued in a public offering.

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No definition available.

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Supplier Finance Program, Termination Period

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No definition available.

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- Definition

This element represents disclosure of the aggregate cash dividends paid to the entity by consolidated subsidiaries.

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Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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No definition available.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Sum of the carrying values as of the balance sheet date of the portions of long-term notes payable due within one year or the operating cycle if longer.

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Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

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Amount of dividends that can be declared or paid without approval of regulatory agency.

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No definition available.

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- Definition

Amount of obligation for supplier finance program.

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Indicates line item in statement of financial position that includes obligation for supplier finance program.

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Period when payment is expected to be made to finance provider or intermediary in supplier finance program, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Financings and Capitalization (Narrative) (Details) - USD ($) $ in Millions	1 Months Ended	6 Months Ended	12 Months Ended
	Dec. 31, 2024	Jun. 30, 2025	Dec. 31, 2023
Financing And Capitalization [Line Items]
Notes payable	$ 65	$ 0
Limitation on payment of stock dividends		8,200
Dividends paid		416
Stock offering program maximum value			$ 1,000
Consumers Energy Company
Financing And Capitalization [Line Items]
Notes payable	65	0
Unrestricted retained earnings		2,400
Consumers Energy Company \| Credit Agreement \| Related Party
Financing And Capitalization [Line Items]
Maximum borrowing capacity	$ 500
Basis spread on variable rate	(0.10%)
Notes payable		$ 0
NorthStar Clean Energy
Financing And Capitalization [Line Items]
Supplier financing program, payment period		135 days
Supplier financing program, termination period		30 days
NorthStar Clean Energy \| NorthStar Clean Energy's Supplier Financing Program
Financing And Capitalization [Line Items]
Supplier Finance Program, Obligation, Statement of Financial Position [Extensible Enumeration]		Accounts payable
Supplier finance obligations		$ 43
Commercial Paper \| Consumers Energy Company
Financing And Capitalization [Line Items]
Short-term debt authorized borrowings		500
Short-term borrowings outstanding		$ 0