Leases - Schedule of Financial Statement Classification of Lease Expenses Reported in Condensed Consolidated Statements of Operations (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Mar. 31, 2021	Mar. 31, 2020
Lessee Lease Description [Line Items]
Total lease cost	$ 161	$ 47	$ 311	$ 130
Cost of sales
Lessee Lease Description [Line Items]
Operating lease cost	13	24	84	87
Finance lease cost	2	6	4	11
Short-term lease cost	49		76
Selling, general and administrative expenses
Lessee Lease Description [Line Items]
Operating lease cost	96	15	144	28
Finance lease cost	$ 1	$ 2	$ 3	$ 4