EQUITY-BASED COMPENSATION - Time-Based Restricted Stock Awards (Details) - Restricted Stock Awards - Time-Based - USD ($) $ / shares in Units, $ in Thousands	9 Months Ended
Sep. 30, 2019	Dec. 31, 2018
Number of Shares
Non-vested at the beginning of period (in shares)	370,152
Granted (in shares)	235,407
Vested (in shares)	(154,801)
Forfeited (in shares)	(2,291)
Non-vested at the end of period (in shares)	448,467
Weighted Average Grant Date Fair Value
Non-vested at the beginning of period (in dollars per share)	$ 13.40
Granted (in dollars per share)	11.32
Vested (in dollars per share)	12.82
Forfeited (in dollars per share)	12.65
Non-vested at the end of period (in dollars per share)	$ 12.51
Aggregate Current Value
Non-vested outstanding	$ 5,202	$ 3,602
Employees
Aggregate Current Value
Vesting period	4 years
Employees \| Period one
Aggregate Current Value
Vesting percentage	20.00%
Employees \| Period two
Aggregate Current Value
Vesting percentage	20.00%
Employees \| Period three
Aggregate Current Value
Vesting percentage	20.00%
Employees \| Period four
Aggregate Current Value
Vesting percentage	40.00%
Executive officers
Aggregate Current Value
Vesting period	3 years
Executive officers \| Period one
Aggregate Current Value
Vesting percentage	25.00%
Executive officers \| Period two
Aggregate Current Value
Vesting percentage	25.00%
Executive officers \| Period three
Aggregate Current Value
Vesting percentage	50.00%

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

No definition available.

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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.

+ References

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-Publisher FASB
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-Paragraph 2
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- Definition

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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- 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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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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- Definition

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

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

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