Other Assets - Prepaid Expenses and Other Current Assets (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Sep. 30, 2020
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Prepaid expenses	$ 5,438	$ 3,612
Other current assets	2,352	1,429
Total prepaid expenses and other current assets	$ 7,790	$ 5,041