LEASES - Components of Lease Expense (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
LEASES
Operating lease costs	$ 2,166	$ 2,159
Finance lease costs:
Amortization of assets	4,723	2,691
Interest on lease liabilities	790	546
Total finance lease costs	5,513	3,237
Variable and short-term lease costs	127	561
Total lease costs	$ 7,806	$ 5,957