CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY - USD ($) $ in Thousands	Total	Ordinary Shares	Additional Paid-in Capital	Accumulated Other Comprehensive Income (Loss)	Retained Earnings
Beginning balance (in shares) at Dec. 31, 2016		49,075,606
Beginning balance at Dec. 31, 2016	$ 975,730	$ 209	$ 774,605	$ (928)	$ 201,844
Increase (Decrease) in Stockholders' Equity
Net income (loss)	(19,425)				(19,425)
Unrealized gains on available-for-sale securities, net of taxes	929			929
Unrealized gains (losses) on derivative contracts, net of taxes	1,617			1,617
Share-based compensation	68,864		68,864
Issuances of shares through employee equity incentive plans (in shares)		1,843,168
Issuances of shares through employee equity incentive plans	7,642	$ 9	7,633
Issuance of shares through employee share purchase plan (in shares)		568,876
Issuance of shares through employee share purchase plan	22,091	$ 3	22,088
Ending balance (in shares) at Dec. 31, 2017		51,487,650
Ending balance at Dec. 31, 2017	1,057,448	$ 221	873,979	1,618	181,630
Increase (Decrease) in Stockholders' Equity
Net income (loss)	134,258				134,258
Unrealized gains on available-for-sale securities, net of taxes	234			234
Unrealized gains (losses) on derivative contracts, net of taxes	(2,903)			(2,903)
Share-based compensation	71,342		71,342
Issuances of shares through employee equity incentive plans (in shares)		1,940,435
Issuances of shares through employee equity incentive plans	14,518	$ 10	14,508
Issuance of shares through employee share purchase plan (in shares)		490,123
Issuance of shares through employee share purchase plan	22,850	$ 2	22,848
Ending balance (in shares) at Dec. 31, 2018		53,918,208
Ending balance at Dec. 31, 2018	1,301,648	$ 233	982,677	(1,051)	319,789
Increase (Decrease) in Stockholders' Equity
Net income (loss)	205,095				205,095
Unrealized gains on available-for-sale securities, net of taxes	1,986			683	1,303
Unrealized gains (losses) on derivative contracts, net of taxes	2,955			2,955
Share-based compensation	112,118		112,118
Issuances of shares through employee equity incentive plans (in shares)		1,535,774
Issuances of shares through employee equity incentive plans	7,599	$ 7	7,592
Issuance of shares through employee share purchase plan (in shares)		309,723
Issuance of shares through employee share purchase plan	24,444	$ 2	24,442
Ending balance (in shares) at Dec. 31, 2019		55,763,705
Ending balance at Dec. 31, 2019	$ 1,655,845	$ 242	$ 1,126,829	$ 2,587	$ 526,187