INCOME TAXES - Reconciliation (Details) $ in Thousands  | 
12 Months Ended | 
|---|---|
| 
 Dec. 31, 2020  
USD ($) 
 | |
| Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns | |
| Balance as of December 31, 2019 | $ 1,192 | 
| Increase due to tax positions of current year | 4 | 
| Balance as of December 31, 2020 | $ 1,196 | 
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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. No definition available. 
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- Definition Amount of unrecognized tax benefits. Reference 1: http://www.xbrl.org/2003/role/disclosureRef 
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- Definition Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return. Reference 1: http://www.xbrl.org/2003/role/disclosureRef 
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