OTHER LONG-TERM LIABILITIES (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Other Liabilities Disclosure [Abstract]
Long-term deferred rent	$ 2,970	$ 5,458
Long-term accrued restructuring	731	1,256
Long-term deferred compensation	5,546	5,464
Total long-term liabilities	$ 9,247	$ 12,178