Financing And Capitalization [Line Items]

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- Definition

Forward Contract Indexed To Issuer's Equity, Aggregate Sales Price

+ References

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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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- Definition

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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- Definition

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

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

Face (par) amount of debt instrument at time of issuance.

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- Definition

Number of shares as a settlement alternative for each freestanding forward contract.

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- Definition

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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- Definition

Amount of dividends available for payment after computation of statutory restrictions on capital surplus.

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

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Financings and Capitalization (Narrative) (Details) - USD ($)		9 Months Ended	12 Months Ended
	Sep. 30, 2019	Sep. 30, 2019	Dec. 31, 2018	Oct. 24, 2019
Financing And Capitalization [Line Items]
Principal balance	$ 2,021,000,000	$ 2,021,000,000
Amount available for dividend payments	$ 5,000,000,000.0	5,000,000,000.0
Common stock dividends from Consumers		$ 396,000,000
Stock offering program maximum value			$ 250,000,000
Settlement required (in shares)	1,039,414	1,039,414
Consumers Energy Company
Financing And Capitalization [Line Items]
Principal balance	$ 926,000,000	$ 926,000,000
Unrestricted retained earnings	1,400,000,000	1,400,000,000
Consumers Energy Company \| Commercial Paper
Financing And Capitalization [Line Items]
Short-term debt, authorized borrowings		500,000,000
Short-term debt	0	$ 0
Forward Contracts
Financing And Capitalization [Line Items]
Forward sales contracts aggregate price	$ 250,000,000
Michigan Strategic Fund Loan Agreement \| Subsequent Event \| Loan Agreement \| Consumers Energy Company
Financing And Capitalization [Line Items]
Principal balance				$ 75,000,000
Michigan Strategic Fund \| MIchigan Strategic Fund Bonds \| Subsequent Event \| Variable Rate Revenue Bonds \| Consumers Energy Company
Financing And Capitalization [Line Items]
Principal balance				$ 75,000,000