OTHER ASSETS (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017	Mar. 31, 2017	Dec. 31, 2016
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Security deposits	$ 5,150	$ 5,304
Restricted cash	4,135	3,837	$ 4,100	$ 4,100
Maintenance agreements, non-current portion	189	362
Other	538	692
Total	$ 10,012	$ 10,195