INTANGIBLE ASSETS - Additional Information (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Goodwill and Intangible Assets Disclosure [Abstract]
Useful life	5 years
Amortization expense	$ 0.3	$ 0.3	$ 0.3
Remaining amortization period	1 year 18 days