Income taxes - Reconciliation of Provision for Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Income Tax Disclosure [Abstract]
Income (loss) before income taxes	$ (52,075)	$ 18,102	$ (8,824)
U.S. statutory income tax rate	21.00%	21.00%	21.00%
Notional U.S. federal income taxes at statutory rate	$ (10,936)	$ 3,801	$ (1,853)
Foreign taxes rate differential	14,651	4,024	(4,216)
Share based compensation	(12,669)	(6,190)	(26,528)
Change in valuation allowance	11,643	6,821	244,344
Return to provision true-ups	2,416	654	(5,204)
Research and Development Credits	(2,216)	(5,243)	(2,333)
State income taxes	1,572	607	(16,679)
Withholding Taxes	273	2,366	384
Non-deductible expenses	(147)	260	357
Unamortized intangible assets	0	0	(189,410)
2020 Cares Act	0	(8,694)	0
Other	1,689	(112)	(456)
Total income tax provision	$ 6,276	$ (1,706)	$ (1,594)
Effective tax rate	(12.10%)	(9.40%)	18.10%