The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)(3)
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Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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-Paragraph 2
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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(2)
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- Definition

The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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-Publisher FASB
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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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Stock-Based Compensation (Schedule Of Restricted Stock Activity) (Details) - $ / shares	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Number of Shares
Granted (in shares)	561,068
Consumers Energy Company
Number of Shares
Granted (in shares)	530,234
Restricted stock
Number of Shares
Granted (in shares)	547,201
Vested (in shares)	(408,011)
Forfeited (in shares)	(22,264)
Weighted-Average Grant Date Fair Value per Share
Granted (in dollars per share)	$ 43.52	$ 45.56	$ 43.57
Vested (in dollars per share)	29.46
Forfeitured (in dollars per share)	$ 57.90
Restricted stock \| Consumers Energy Company
Number of Shares
Granted (in shares)	517,141
Vested (in shares)	(388,009)
Forfeited (in shares)	(21,780)
Weighted-Average Grant Date Fair Value per Share
Granted (in dollars per share)	$ 42.85	45.53	43.57
Vested (in dollars per share)	29.55
Forfeitured (in dollars per share)	$ 58.01
Restricted stock units
Number of Shares
Granted (in shares)	13,867
Vested (in shares)	(15,577)
Forfeited (in shares)	0
Weighted-Average Grant Date Fair Value per Share
Granted (in dollars per share)	$ 54.11	49.76	50.35
Vested (in dollars per share)	$ 48.15
Restricted stock units \| Consumers Energy Company
Number of Shares
Granted (in shares)	13,093
Vested (in shares)	(14,891)
Forfeited (in shares)	0
Weighted-Average Grant Date Fair Value per Share
Granted (in dollars per share)	$ 53.93	$ 49.70	$ 51.15
Vested (in dollars per share)	$ 48.09
Restricted Stock and Restricted Stock Units
Number of Shares
Nonvested, at beginning of period (in shares)	817,357
Nonvested, at end of period (in shares)	932,573	817,357
Weighted-Average Grant Date Fair Value per Share
Weighted-average grant date fair value per share, at beginning of period (in dollars per share)	$ 51.68
Weighted-average grant date fair value per share, at end of period (in dollars per share)	$ 56.56	$ 51.68
Restricted Stock and Restricted Stock Units \| Consumers Energy Company
Number of Shares
Nonvested, at beginning of period (in shares)	781,531
Nonvested, at end of period (in shares)	887,085	781,531
Weighted-Average Grant Date Fair Value per Share
Weighted-average grant date fair value per share, at beginning of period (in dollars per share)	$ 51.73
Weighted-average grant date fair value per share, at end of period (in dollars per share)	$ 56.19	$ 51.73