Stock-based compensation - Reserved For Issuance (Details) shares in Thousands	9 Months Ended
Jun. 30, 2023 shares
Share-Based Compensation Arrangement By Share-based Payment Award, Outstanding [Roll Forward]
Beginning balance (in shares)	507
Additional shares authorized (in shares)	249
Shares issued during the period (in shares)	(132)
Ending balance (in shares)	624

Share-Based Compensation Arrangement By Share-based Payment Award, Outstanding

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- Definition

Aggregate number of common shares reserved for future issuance.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.29)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1

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- Definition

Number of additional shares authorized for issuance under share-based payment arrangement.

+ References

No definition available.

+ Details

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- Definition

Number of shares issued under share-based payment arrangement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480429/718-10-50-2

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