Long-term debt - Future principal payments due (Details) $ in Thousands	Sep. 30, 2022 USD ($)
Future principal payments due
2023	$ 6,544
2024	3,851
Total future payments	$ 10,395

Amount, excluding unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

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Name:	us-gaap_LongTermDebt
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant