Accrued Liabilities and Accounts Payable - Summary of accrued expenses reflected on the company's balance sheet (Detail) - USD ($) $ in Thousands	Dec. 31, 2021	Sep. 30, 2021
Accrued Liabilities, Current [Abstract]
Accrued bonus liabilities	$ 801	$ 2,738
Accrued sub-advisor fees	623	628
Other accrued expenses	1,040	785
Total accrued liabilities and accounts payable	$ 2,464	$ 4,151