EQUITY-BASED COMPENSATION - Performance-Based Restricted Stock Awards (Details) - Restricted Stock Awards - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
Mar. 31, 2021	Dec. 31, 2020
Maximum \| Executive officers
Aggregate Current Value
Number of shares may earn, as multiple of shares granted	200.00%
Minimum \| Executive officers
Aggregate Current Value
Number of shares may earn, as multiple of shares granted	0.00%
Performance-based restricted stock
Number of Shares
Non-vested at the beginning of period (in shares)	922,239
Granted (in shares)	259,728
Vested (in shares)	(182,480)
Forfeited (in shares)	(60,823)
Non-vested at the end of period (in shares)	938,664
Weighted Average Grant Date Fair Value
Non-vested at the beginning of period (in dollars per share)	$ 11.65
Granted (in dollars per share)	14.05
Vested (in dollars per share)	13.73
Forfeited (in dollars per share)	13.73
Non-vested at the end of period (in dollars per share)	$ 11.78
Aggregate Current Value
Non-vested outstanding	$ 9,499	$ 8,309
Vesting period	3 years

No definition available.

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Represents the current value of equity-based compensation awards not vested. Excludes stock and unit options.

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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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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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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).

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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).

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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.

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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.

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

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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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Percentage of vesting of award under share-based payment arrangement.

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