LEASES - Assets and liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Assets:
Operating lease right-of-use assets	$ 33,250	$ 33,850
Operating Lease, Right-of-Use Asset, Statement of Financial Position [Extensible List]	Operating lease right-of-use assets
Liabilities
Current portion of operating lease liabilities	$ 10,215	10,625
Long-term operating lease liabilities	$ 27,529	$ 28,378
Operating Lease, Liability, Noncurrent, Statement of Financial Position [Extensible List]	Long-term operating lease liabilities
Present value of lease liabilities	$ 37,744