Accrued Expenses and Other Liabilities - Accrued Expenses and Other Current Liabilities (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Sep. 30, 2021
Accrued expenses and other current liabilities
Compensation-related	$ 62,813	$ 24,898
Uncertain tax positions	2,773	1,964
Professional fees	5,799	4,317
Income taxes payable	4,448	5,394
Business Combination, Acquisition Related Costs	4,102	0
Other Accrued Liabilities, Current	10,188	8,755
Total accrued expenses and other current liabilities	$ 90,123	$ 45,328