Fixed assets - Summary of Fixed Assets, Net (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Property Plant And Equipment [Line Items]
Fixed assets	$ 3,717	$ 3,683
Less: accumulated depreciation and amortization	2,518	1,741
Fixed assets, net	1,199	1,942
Furniture and fixtures [Member]
Property Plant And Equipment [Line Items]
Fixed assets	1,407	1,407
Computer and office equipment [Member]
Property Plant And Equipment [Line Items]
Fixed assets	1,855	1,784
Computer software [Member]
Property Plant And Equipment [Line Items]
Fixed assets	375	412
Leasehold improvements [Member]
Property Plant And Equipment [Line Items]
Fixed assets	$ 80	$ 80