Fixed assets - Summary of Fixed Assets, Net (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Property Plant And Equipment [Line Items]
Fixed assets	$ 3,759	$ 3,717
Less: accumulated depreciation and amortization	2,677	2,518
Fixed assets, net	1,082	1,199
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	1,897	1,855
Computer software [Member]
Property Plant And Equipment [Line Items]
Fixed assets	375	375
Leasehold improvements [Member]
Property Plant And Equipment [Line Items]
Fixed assets	$ 80	$ 80

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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