Financial (expense)/income, net (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Financial (expense)/income, net
Interest income	$ 393	$ 661	$ 1,142	$ 2,138
Foreign exchange (loss)/gain, net	(2,672)	1,105	(3,797)	709
Bank charges	(34)	(214)	(248)	(408)
Total financial (expense)/income, net	$ (2,313)	$ 1,552	$ (2,903)	$ 2,439