EQUITY-BASED COMPENSATION - Performance-Based Restricted Stock Awards (Details) - Restricted Stock Awards - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
Mar. 31, 2020	Dec. 31, 2019
Performance-Based
Number of Shares
Non-vested at the beginning of period (in shares)	755,991
Granted (in shares)	376,609
Forfeited (in shares)	(210,361)
Non-vested at the end of period (in shares)	922,239
Weighted Average Grant Date Fair Value
Non-vested at the beginning of period (in dollars per share)	$ 14.31
Granted (in dollars per share)	9.38
Forfeited (in dollars per share)	17.13
Non-vested at the end of period (in dollars per share)	$ 11.65
Aggregate Current Value
Non-vested outstanding	$ 3,744	$ 9,329
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%

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Represents the current value of equity-based compensation awards not vested. Excludes stock and 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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- 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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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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Percentage of vesting of award under share-based payment arrangement.

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