LEASES - Summary of supplemental balance sheet information (Details) $ in Thousands	Sep. 30, 2020 USD ($)
Operating Leases:
Operating right-of-use assets	$ 161,627
Lease Liabilities:
Current portion of operating lease liabilities	31,848
Long-term operating lease liabilities	136,054
Total operating lease liabilities	167,902
Finance Leases:
Property, plant and equipment, net	$ 18,774
Finance Lease, Right-of-Use Asset, Statement of Financial Position [Extensible List]	us-gaap:PropertyPlantAndEquipmentNet
Lease Liabilities:
Notes payable and current portion of long-term debt	$ 3,352
Long-term debt, net	15,339
Total financing lease liabilities	$ 18,691
Finance Lease, Liability, Current, Statement of Financial Position [Extensible List]	us-gaap:LongTermDebtCurrent
Finance Lease, Liability, Noncurrent, Statement of Financial Position [Extensible List]	us-gaap:LongTermDebtNoncurrent
Accumulated depreciation	$ 2,383