Trade Accounts and Financing Receivables - Financing Receivables (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Sep. 30, 2020
Accounts Notes And Loans Receivable [Line Items]
Total financing receivables	$ 8,682	$ 184
Total unearned income	(31)
Total financing receivables, net of unearned income	8,651	184
Less current portion	(6,497)	(184)
Non-current notes receivable	2,154
Promissory Notes
Accounts Notes And Loans Receivable [Line Items]
Total financing receivables	5,708	$ 184
Sales-type Lease
Accounts Notes And Loans Receivable [Line Items]
Total financing receivables	2,974
Total unearned income	$ (31)