| INCOME TAXES - Change in Deferred Tax Asset Valuation Allowance (Details) $ in Thousands | 12 Months Ended | 
|---|---|
| Dec. 31, 2018  USD ($) | |
| Changes in deferred tax asset valuation allowance: | |
| December 31, 2017 | $ 106,466 | 
| December 31, 2018 | 104,705 | 
| Decrease due to current year operations | |
| Changes in deferred tax asset valuation allowance: | |
| Change in valuation allowance | $ (1,761) | 
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- References No definition available. 
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- Definition Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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- Definition Amount of increase (decrease) in the valuation allowance for a specified deferred tax asset. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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- Details 
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