STOCK BASED COMPENSATION - Summary of Restricted Stock and Performance Share Activity (Details) - $ / shares	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Performance share units
Number of shares
Balance	99,400
Granted	187,978
Performance adjustment	(4,155)
Balance	283,223	99,400
Weighted-average grant date fair value per share
Balance	$ 15.90
Granted	28.49	$ 15.90	$ 0
Performance adjustment	15.90
Balance	$ 24.26	$ 15.90
Restricted stock units
Number of shares
Balance	849,679
Granted	767,634
Vested	(335,524)
Forfeited	(39,402)
Balance	1,242,387	849,679
Weighted-average grant date fair value per share
Balance	$ 17.10
Granted	21.35
Vested	17.85
Forfeited	20.20
Balance	$ 19.42	$ 17.10

The weighted average fair value at grant date for nonvested equity-based awards pertaining to performance adjustment.

No definition available.

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- Definition

Number of share representing performance adjustments relating to equity-based payment instruments, excluding stock (or unit) options.

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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
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-SubTopic 10
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- Definition

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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- Definition

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).

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- Definition

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).

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- Definition

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.

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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.

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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.

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

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-Name Accounting Standards Codification
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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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