Revenue - Revenue from External Customers by Geographic Region (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Disaggregation of Revenue [Line Items]
Total revenue	$ 83,742	$ 102,398	$ 209,677	$ 302,970
China
Disaggregation of Revenue [Line Items]
Total revenue	26,026	57,087	66,209	178,661
Americas
Disaggregation of Revenue [Line Items]
Total revenue	10,561	17,201	21,750	51,622
Rest of world
Disaggregation of Revenue [Line Items]
Total revenue	$ 47,155	$ 28,110	$ 121,718	$ 72,687