Balance sheet components - Inventory (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Sep. 30, 2022
Balance Sheet Related Disclosures [Abstract]
Raw materials	$ 33,558	$ 28,787
Work-in-process	3,610	2,866
Finished goods	7,429	7,654
Total inventories	$ 44,597	$ 39,307

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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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