Summary of Significant Accounting Policies - ROU Assets and Lease Liability (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Sep. 30, 2021
Accounting Policies [Abstract]
ROU asset	$ 208	$ 309
Operating Lease, Right-of-Use Asset, Statement of Financial Position [Extensible Enumeration]	Other non-current assets, net	Other non-current assets, net
Current lease liability	$ 212	$ 314
Operating Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration]	Other current liabilities	Other current liabilities