ACCRUED LIABILITIES (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
ACCRUED LIABILITIES
Accrued compensation	$ 11,730	$ 13,196
Accrued royalties	21,703	20,555
Other accrued liabilities	25,965	29,180
Total accrued liabilities	$ 59,398	$ 62,931