Balance sheet components - Summary of Inventory (Detail) - USD ($) $ in Thousands	Sep. 30, 2020	Sep. 30, 2019
Balance Sheet Related Disclosures [Abstract]
Raw Materials	$ 9,237	$ 4,900
Work-in-process	2,021	1,157
Finished Goods	1,031	1,273
Total inventories	$ 12,289	$ 7,330

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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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Amount before valuation and LIFO reserves of raw materials expected to be sold, or consumed within one year or operating cycle, if longer.

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

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