ADOPTION OF ASU NO. 2016-02, LEASES (Lease Costs) (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2019 USD ($)
Lessee, Lease, Description [Line Items]
Operating lease cost	$ 3,122
Variable lease cost	1,250
Short-term lease cost	4,410
Total lease cost	8,782
Lease operating expense
Lessee, Lease, Description [Line Items]
Total lease cost	4,241
General and administrative expense
Lessee, Lease, Description [Line Items]
Total lease cost	$ 4,541