Leases - Summary of Future Lease Payments (Details) $ in Thousands	Sep. 30, 2020 USD ($)
Operating leases
2021	$ 170,522
2022	131,701
2023	95,956
2024	66,164
2025	42,216
Thereafter	95,944
Total undiscounted lease payments	602,503
Less: imputed interest	54,861
Present value of lease liabilities	547,642
Finance leases
2021	193
2022	192
2023	192
2024	192
2025	160
Total undiscounted lease payments	929
Less: imputed interest	65
Present value of lease liabilities	$ 864