Balance sheet components - Inventory (Detail) - USD ($) $ in Thousands	Mar. 31, 2022	Sep. 30, 2021
Balance Sheet Related Disclosures [Abstract]
Raw materials	$ 31,975	$ 18,778
Work-in-process	3,048	4,837
Finished goods	9,568	8,185
Total inventories	$ 44,591	$ 31,800

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Amount before valuation and LIFO reserves of completed merchandise or goods expected to be sold within one year or operating cycle, if longer.

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