ACCOUNTS PAYABLE AND ACCRUED LIABILITIES (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Payables and Accruals [Abstract]
Accounts payable	$ 4,344	$ 6,296
Accrued clinical, development and other expenses	6,256	5,743
Accrued compensation and benefits	3,021	2,923
Other current liabilities	23	40
Total accounts payable and accrued liabilities	$ 13,644	$ 15,002