Balance sheet components - Inventory (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Sep. 30, 2022
Balance Sheet Related Disclosures [Abstract]
Raw materials	$ 30,896	$ 28,787
Work-in-process	611	2,866
Finished goods	4,847	7,654
Total inventories	$ 36,354	$ 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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Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

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Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 852
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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.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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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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