LEASES AND RIGHT OF USE ASSETS - Components of Lease Expense (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2019
LEASES AND RIGHT OF USE ASSETS
Operating lease costs	$ 2,355	$ 6,870
Finance lease costs:
Amortization of assets	3,903	9,553
Interest on lease liabilities	671	1,820
Total finance lease costs	4,574	11,373
Variable and short-term lease costs	71	844
Total lease costs	$ 7,000	$ 19,087