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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share 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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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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STOCK-BASED COMPENSATION - 2015 EIP Restricted Stock Units (Details) - 2015 EIP Plan - Restricted Stock Units - USD ($) $ / shares in Units, $ in Thousands							12 Months Ended
	Jul. 15, 2020	Feb. 25, 2020	May 15, 2019	Mar. 04, 2019	May 15, 2018	Feb. 27, 2018	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Stock Awards
Number of common shares outstanding in respect of RSUs							373,588	326,247
Vesting period of awards							3 years
Number of Shares
Balance at the beginning of the period (in shares)							162,096	149,170	220,129
Granted (in shares)	42,642	173,749	29,580	106,079	14,268	37,436	221,903	140,914	51,704
Vested (in shares)	(29,580)		(14,268)				(83,675)	(127,988)	(122,663)
Forfeited (in shares)							(1,490)
Balance at the end of the period (in shares)							298,834	162,096	149,170
Weighted Average Fair Value
Balance at the beginning of the period (in dollars per share)							$ 9.26	$ 12.42	$ 11.01
Granted (in dollars per share)							6.80	8.50	14.84
Vested (in dollars per share)							9.07	12.10	10.92
Forfeited (in dollars per share)							8.39
Balance at the end of the period (in dollars per share)							$ 7.49	$ 9.26	$ 12.42
Weighted-average remaining contractual life							1 year 7 months 2 days
Additional disclosures
Total fair value of shares vested							$ 550	$ 1,235	$ 1,694
Unrecognized compensation cost related to nonvested stock awards
Unrecognized compensation cost							$ 849
Weighted-average period for recognition of unrecognized compensation cost							1 year 7 months 2 days
General and Administrative Expense
Additional disclosures
Recognized nonvested stock amortization expense							$ 1,239	$ 1,207	$ 1,489
Vested RSUs
Number of Shares
Number of shares vested							505,898
Weighted Average Grant Date Price, Vested							$ 11.07