SHARE BASED AND OTHER COMPENSATION - Summary of stock option activity (Details) - Omnibus Incentive Plan 2016 - $ / shares	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Number of Options
Outstanding beginning balance (in shares)	3,588,350
Forfeited or canceled (in shares)	(132,325)
Outstanding ending balance (in shares)	3,456,025
Weighted Average Exercise Price
Outstanding beginning (in dollars per share)	$ 4.05
Forfeited or canceled (in dollars per share)	3.14
Outstanding ending (in dollars per share)	$ 4.05
Stock Options Outstanding and Exercisable
Number of options vested/exercisable (in shares)	3,416,093		3,487,792
Weighted average remaining contractual life (Years)	7 years 2 months 12 days	7 years 2 months 12 days

The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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-Name Accounting Standards Codification
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-SubTopic 10
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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.

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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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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 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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