LEASES - Summary of Future Maturities of Lease Payments for Operating Leases (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Sep. 30, 2020
Operating Leases
2020	$ 9,771
2022	35,363
2023	27,677
2024	20,719
2025	18,673
2026	12,689
Thereafter	64,282
Total lease payments	189,174
Less: Imputed Interest	(33,690)
Present value of lease liabilities	155,484	$ 167,902
Finance Leases
2021	1,227
2022	3,166
2023	2,832
2024	2,244
2025	2,077
2026	2,075
Thereafter	7,777
Total lease payments	21,398
Less: Imputed Interest	(4,052)
Present value of lease liabilities	$ 17,346	$ 18,691