Other liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Other current liabilities
Lease liability	$ 4,596	$ 4,198
Total other current liabilities	4,596	4,198
Other non-current liabilities
Lease liability	42,143	43,409
Other	1,001	1,001
Total other non-current liabilities	$ 43,144	$ 44,410