SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Accounting Policies [Line Items]
Foreign currency translation adjustments	$ (5,489)	$ (5,691)	$ (2,894)
Pension liability, net of tax	(11,080)	(12,776)	(15,136)
Total accumulated other comprehensive loss	$ (16,569)	$ (18,467)	$ (18,030)