ACCRUED EXPENSES (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
ACCRUED EXPENSES [Abstract]
Accrued compensation and benefits	$ 4,337	$ 3,114
Accrued rent and real estate taxes	3,057	3,151
Other accrued expenses	3,211	5,506
Accrued expenses	$ 10,605	$ 11,771