Balance sheet components - Receivable (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Sep. 30, 2022
Balance Sheet Related Disclosures [Abstract]
Trade receivables	$ 43,202	$ 35,706
Other receivables	5,314	4,822
Allowance for doubtful accounts	(329)	(234)
Accounts receivable, net	$ 48,187	$ 40,294

Amount, before allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business, classified as current.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount, after allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business, classified as current.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of allowance for credit loss on accounts receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 13
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No definition available.

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Amount, before allowance, of receivables classified as other, due within one year or the operating cycle, if longer.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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