Stock-based compensation - Narrative (Details) - Equity Incentive Plan 2019 - shares	Nov. 20, 2019	Sep. 30, 2020	Nov. 30, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares reserved for future issuance (in shares)			5,700,000
Additional shares reserved for future issuance (up to) (in shares)		5,800,000	5,800,000
Termination period from date of adoption	10 years

Common Stock, Additional Capital Shares Reserved for Future Issuance

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- Definition

Share-based Compensation Arrangement by Share-based Compensation Award, Termination Period From Date Of Adoption

+ References

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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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.29)
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

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