SHARE INCENTIVE PLANS - Share-based compensation (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Share-based compensation expense
Total share-based compensation expense	$ 112,118	$ 71,342	$ 68,864
Total unrecognized share-based compensation costs related to non-vested awards	$ 235,400
Weighted average period for recognition of unrecognized share-based compensation costs (in years)	2 years 8 months 8 days
Share options
Share-based compensation expense
Total share-based compensation expense	$ 8	12	115
ESPP
Share-based compensation expense
Total share-based compensation expense	7,161	6,378	6,232
RSU
Share-based compensation expense
Total share-based compensation expense	102,898	64,059	62,517
PSU
Share-based compensation expense
Total share-based compensation expense	2,051	893	0
Cost of goods sold
Share-based compensation expense
Total share-based compensation expense	3,493	1,950	2,000
Research and development
Share-based compensation expense
Total share-based compensation expense	61,315	38,922	40,278
Sales and marketing
Share-based compensation expense
Total share-based compensation expense	26,614	17,042	15,693
General and administrative
Share-based compensation expense
Total share-based compensation expense	$ 20,696	$ 13,428	$ 10,893

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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