SHARE-BASED COMPENSATION - Options Activity (Details) - USD ($)	6 Months Ended
Jun. 30, 2019
Options activity [Roll Forward]
Options beginning	755,210
Options granted	0
Options exercised	(180,300)
Options forfeited	0
Options expired	(29,828)
Options ending	545,082
Weighted average exercise price - beginning	$ 9.42
Weighted average exercise price - options granted	0
Weighted average exercise price - options exercised	1.34
Weighted average exercise price - options forfeited	0
Weighted average exercise price - options expired	10.53
Weighted average exercise price - ending	$ 12.03
Weighted Average Remaining Contractual Term (Years) Options	1 year 4 months 24 days
Intrinsic Value Options	$ 0
Options vested and expected to vest	545,082
Options vested and exercisable	545,082
Weighted average exercise price options vested and expected to vest	$ 12.03
Weighted average exercise price options vested and exerciable	$ 12.03
Weighted average remaining contractual period (Years) options vested and expected to vest	1 year 4 months 24 days
Weighted average remaining contractual period (years) options vested and exercisable	1 year 4 months 24 days
Intrinsic value options vested and expected to vest	$ 0
Intrinsic value options vested and exercisable	$ 0
Weighted average remaining recognition period in years	0 years
Unamortized compensation expense, net of estimated forfeitures	$ 0

Unamortized compensation expense for options net of estimated forfeitures.

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Period over which the unamortized compensation expense will be recognized for options.

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Number of options or other stock instruments for which the right to exercise has lapsed under the terms of the plan agreements.

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For presentations that combine terminations, the number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan or that expired.

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Net number of share options (or share units) granted during the period.

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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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Number of options outstanding, including both vested and non-vested options.

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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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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Amount by which current fair value of underlying stock exceeds exercise price of fully vested and expected to vest exercisable or convertible options. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Number of fully vested and expected to vest exercisable options that may be converted into shares under option plan. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Weighted-average exercise price, at which grantee can acquire shares reserved for issuance, for fully vested and expected to vest exercisable or convertible options. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Amount by which current fair value of underlying stock exceeds exercise price of fully vested and expected to vest options outstanding. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Number of fully vested and expected to vest options outstanding that can be converted into shares under option plan. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Weighted-average exercise price, at which grantee can acquire shares reserved for issuance, for fully vested and expected to vest options outstanding. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options of the plan that expired.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average remaining contractual term for fully vested and expected to vest exercisable or convertible options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Weighted average remaining contractual term for fully vested and expected to vest options outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Number of share options (or share units) exercised during the current period.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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