Notes payable - Other notes (Details) - Other Notes $ in Millions	Dec. 31, 2022 USD ($)
Notes payable
Principal amount	$ 7.5
Interest rate	15.00%

Face (par) amount of debt instrument at time of issuance.

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