ACCRUED LIABILITIES (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
ACCRUED LIABILITIES
Accrued compensation	$ 10,604	$ 11,730
Accrued royalties	18,486	21,703
Other accrued liabilities	23,962	25,965
Total accrued liabilities	$ 53,052	$ 59,398