Share Option Plans and ESPP - Schedule of Non-cash Share-Based Compensation Expenses Related to Company's Equity-Based Awards (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation expense	$ 25,758	$ 20,121	$ 72,502	$ 55,448	$ 75,721
Cost of revenues
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation expense	808	767	2,368	1,916	2,221
Research, development and clinical trials
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation expense	7,761	5,101	21,390	12,275	18,125
Sales and marketing
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation expense	5,806	4,677	16,706	13,061	17,672
General and administrative
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total share-based compensation expense	$ 11,383	$ 9,576	$ 32,038	$ 28,196	$ 37,703