EMPLOYEE BENEFIT PLANS - 401(K) Savings Plans (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2018 USD ($) plan	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
Retirement Benefits [Abstract]
Number of savings plan | plan	2
Provision for profit sharing contributions	$ 825	$ 395	$ 712
Provision for matching 401(k) savings plan contributions	3,153	$ 2,594	$ 2,248
Deferred compensation liability	$ 265