DERIVATIVE INSTRUMENTS - CHANGES IN DERIVATIVE WARRANT LIABILITY (Details) - USD ($) $ in Thousands |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2016 |
Dec. 31, 2015 |
Dec. 31, 2014 |
|
| Changes in Derivative Warrant Liability | |||
| Balance at beginning of year | $ 1,907 | ||
| Issuance of warrants | $ 6,848 | ||
| Fair value of derivative warrant liability reclassified to additional paid-in capital | $ (16,121) | ||
| Balance at end of period | 1,314 | 1,907 | |
| Warrants | |||
| Changes in Derivative Warrant Liability | |||
| Balance at beginning of year | 1,907 | 7,224 | |
| Issuance of warrants | 6,848 | ||
| (Decrease) increase in the fair value of the warrants | (593) | 10,804 | 376 |
| Fair value of derivative warrant liability reclassified to additional paid-in capital | (16,121) | ||
| Balance at end of period | $ 1,314 | $ 1,907 | $ 7,224 |