LEASE ASSETS AND LIABILITIES (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
ASSETS.
Operating lease assets	$ 97,866	$ 120,820
Finance lease assets	8,103	12,659
Total leased assets	105,969	133,479
Current
Operating Lease, Liability, Current	42,643	43,651
Finance Lease, Liability, Current	$ 3,669	$ 6,193
Finance Lease, Liability, Current, Statement of Financial Position [Extensible List]	Other current liabilities	Other current liabilities
Non-current
Operating Lease, Liability, Noncurrent	$ 73,172	$ 98,277
Finance Lease, Liability, Noncurrent	$ 2,999	$ 4,763
Finance Lease, Liability, Noncurrent, Statement of Financial Position [Extensible List]	Other liabilities, noncurrent	Other liabilities, noncurrent
Total lease liabilities	$ 122,483	$ 152,884