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

No definition available.

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- Definition

Debt Covenant, Interest Rate Coverage Ratio Multiplier Minimum To Issue First Mortgage Bonds

+ References

No definition available.

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- Definition

Financing And Capitalization [Line Items]

+ References

No definition available.

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- Definition

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

+ References

No definition available.

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- Definition

Forward Contract Indexed To Issuer's Equity, Settlement Rate Per Share

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No definition available.

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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.

+ References

No definition available.

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- Definition

Stock Issued During Period, Shares, Settlement Of Forward Contract Indexed To Issuer's Equity

+ References

No definition available.

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- Definition

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

+ References

No definition available.

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 3
-Subparagraph (SX 210.12-04(b))
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- Definition

Face amount or stated value per share of common stock.

+ References

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- Definition

The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

+ References

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- Definition

Fair value amount of debt instrument that was repurchased.

+ References

No definition available.

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- Definition

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

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 40
-Section 50
-Paragraph 5
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- Definition

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.

+ References

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- Definition

Face amount or stated value per share of preferred stock nonredeemable or redeemable solely at the option of the issuer.

+ References

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- Definition

The maximum number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) permitted to be issued by an entity's charter and bylaws.

+ References

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- Definition

The cash inflow from the additional capital contribution to the entity.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (a)
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- Definition

The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3291-108585

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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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-SubTopic 10
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- Definition

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

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section S99
-Paragraph 1
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- Definition

Percentage of the Variable Interest Entity's (VIE) voting interest owned by (or beneficial interest in) the reporting entity (directly or indirectly).

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-Publisher FASB
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-SubTopic 10
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-Paragraph 5A
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Financings And Capitalization (Narrative) (Details) - USD ($)	1 Months Ended		12 Months Ended			24 Months Ended
	Sep. 30, 2020	Jul. 31, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2019
Financing And Capitalization [Line Items]
Debt retirement, principal			$ 1,325,000,000
Limitation on payment of stock dividends			5,500,000,000
Dividends paid			$ 637,000,000
Common stock authorized (in shares)			350,000,000.0	350,000,000.0		350,000,000.0
Par value of common stock (in dollars per share)			$ 0.01
Preferred stock authorized (in shares)			10,000,000
Par value of preferred stock (in dollars per share)			$ 0.01
Issuance of common stock, net of issuance costs			$ 253,000,000	$ 12,000,000	$ 41,000,000
Stock offering program maximum value			$ 500,000,000
Number of shares required to settle forward contracts (in shares)			6,666
Variable Interest Entity, Primary Beneficiary \| Aviator Wind
Financing And Capitalization [Line Items]
Ownership interest	51.00%	51.00%
Debt retirement, principal	$ 492,000,000
Consumers Energy Company
Financing And Capitalization [Line Items]
Debt retirement, principal			$ 1,025,000,000
Interest rate coverage ratio multiplier minimum to issue FMBs			200.00%
Unrestricted retained earnings			$ 1,600,000,000
Common stock authorized (in shares)			125,000,000.0	125,000,000.0		125,000,000.0
Consumers Energy Company \| Credit Agreement
Financing And Capitalization [Line Items]
Maximum borrowing capacity			$ 350,000,000
Consumers Energy Company \| Commercial Paper
Financing And Capitalization [Line Items]
Short-term debt authorized borrowings			500,000,000
Short-term borrowings outstanding			$ 0
Tax Exempt Revenue Bonds Due 2035 \| Consumers Energy Company \| Tax Exempt Revenue Bonds
Financing And Capitalization [Line Items]
Debt repurchased		$ 35,000,000
Forward Contracts
Financing And Capitalization [Line Items]
Forward contract indexed to issuer's equity						$ 250,000,000
Settlement Of Forward Contracts
Financing And Capitalization [Line Items]
Settlement of forward contract indexed to issuer's equity (in shares)			4,879,022
Settlement rate per share (in dollars per share)			$ 48.86
Issuance of common stock, net of issuance costs			$ 238,000,000