LEASES - Components of Lease Expense (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Leases [Abstract]
Short-term operating lease cost	$ 545	$ 1,128	$ 1,691	$ 2,812
Long-term operating lease cost	1,193	1,149	2,430	2,299
Total operating lease cost	1,738	2,277	4,121	5,111
Amortization of right-of-use asset	1,625	1,464	3,213	2,719
Interest on lease liabilities	84	88	167	196
Total finance lease cost	$ 1,709	$ 1,552	$ 3,380	$ 2,915