v3.8.0.1
SIGNIFICANT ACCOUNTING POLICIES - Research and Development Costs (Details) - USD ($)
$ in Thousands
12 Months Ended
Dec. 31, 2017
Dec. 31, 2016
Dec. 31, 2015
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]      
Research and development $ 3,423 $ 2,223 $ 1,789
Research and Development - Product      
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]      
Research and development obligation   0 $ 1,517
Payment for research and development   341  
Research and development obligation reversed   $ 889