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SHARE-BASED PAYMENTS - Schedule of Valuation Assumptions (Details) - $ / shares | 12 Months Ended
--- | ---
Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
Compensation Plan |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Expected life | 4 years 12 months | 5 years | 5 years
Expected volatility | 63.00% |  | 75.10%
Expected dividend yield | 0.00% | 0.00% | 0.00%
Weighted Average Expected Life Of Option | 5 years | 5 years | 5 years
Weighted-average expected life of option | 4 years 12 months | 5 years | 5 years
Weighted-average grant date fair value (in dollars per share) | $ 1.20 |  |
Minimum | Compensation Plan |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Risk-free interest rate | 1.93% | 1.03% |
Expected volatility |  | 64.70% |
Weighted-average grant date fair value (in dollars per share) |  | $ 1.22 |
Minimum | Business Combinations and Asset Acquisitions |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Risk-free interest rate |  |  | 0.00%
Expected life |  |  | 18 days
Expected volatility |  |  | 18.47%
Weighted-average expected life of option |  |  | 18 days
Maximum | Compensation Plan |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Risk-free interest rate |  | 1.43% |
Expected volatility |  | 74.80% |
Weighted-average grant date fair value (in dollars per share) |  | $ 1.23 |
Maximum | Business Combinations and Asset Acquisitions |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Risk-free interest rate |  |  | 2.35%
Expected life |  |  | 10 years
Expected volatility |  |  | 93.31%
Weighted-average expected life of option |  |  | 10 years

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- Definition The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (f)(2)(iii) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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- Definition The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (f)(2)(ii) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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- Definition The risk-free interest rate assumption that is used in valuing an option on its own shares. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (f)(2)(iv) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Definition The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (d)(1) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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- Definition Expected term of share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (f)(2)(i) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 14.D.2) -URI http://asc.fasb.org/extlink&oid=27013229&loc=d3e301413-122809 + Details
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