FAIR VALUE MEASUREMENTS (Financial Liabilities at Fair Value on a Recurring Basis) (Details) - Recurring - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Liabilities, Fair Value Disclosure [Abstract]
Total financial liabilities measured at fair value on a recurring basis	$ 0	$ 3,789
Restricted Stock
Liabilities, Fair Value Disclosure [Abstract]
Performance-based equity awards		3,789
Level 1
Liabilities, Fair Value Disclosure [Abstract]
Total financial liabilities measured at fair value on a recurring basis		3,789
Level 1 | Restricted Stock
Liabilities, Fair Value Disclosure [Abstract]
Performance-based equity awards		3,789
Level 2
Liabilities, Fair Value Disclosure [Abstract]
Total financial liabilities measured at fair value on a recurring basis		0
Level 2 | Restricted Stock
Liabilities, Fair Value Disclosure [Abstract]
Performance-based equity awards		0
Level 3
Liabilities, Fair Value Disclosure [Abstract]
Total financial liabilities measured at fair value on a recurring basis		0
Level 3 | Restricted Stock
Liabilities, Fair Value Disclosure [Abstract]
Performance-based equity awards		$ 0