CONSOLIDATED STATEMENTS OF CHANGES IN SHAREHOLDERS' EQUITY - USD ($) $ in Thousands	Total	Cumulative Effect, Period of Adoption, Adjustment	Ordinary shares	Additional paid-in capital	Additional paid-in capital Cumulative Effect, Period of Adoption, Adjustment	Accumulated other comprehensive loss	Retained earnings (accumulated deficit)	Retained earnings (accumulated deficit) Cumulative Effect, Period of Adoption, Adjustment
Beginning balance (in shares) at Dec. 31, 2019			99,528,435
Beginning balance at Dec. 31, 2019	$ 217,790			$ 871,442		$ (2,767)	$ (650,885)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Share-based compensation to employees	16,557			16,557
Exercise of options and vested RSUs (in shares)			834,538
Exercise of options and vested RSUs	4,511			4,511
Other comprehensive income (loss), net of tax benefit	(862)					(862)
Net income (loss)	3,952						3,952
Ending balance (in shares) at Mar. 31, 2020			100,362,973
Ending balance at Mar. 31, 2020	241,948			892,510		(3,629)	(646,933)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Other comprehensive income (loss), tax benefit	0
Beginning balance (in shares) at Dec. 31, 2019			99,528,435
Beginning balance at Dec. 31, 2019	217,790			871,442		(2,767)	(650,885)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	14,891
Ending balance (in shares) at Sep. 30, 2020			101,728,327
Ending balance at Sep. 30, 2020	307,037			946,267		(3,236)	(635,994)
Beginning balance (in shares) at Dec. 31, 2019			99,528,435
Beginning balance at Dec. 31, 2019	$ 217,790			871,442		(2,767)	(650,885)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Accounting standards update [extensible enumeration]	Accounting Standards Update 2020-06 [Member]
Net income (loss)	$ 19,808
Ending balance (in shares) at Dec. 31, 2020			102,334,276
Ending balance at Dec. 31, 2020	476,526	$ (128,972)		1,111,435	$ (132,474)	(3,832)	(631,077)	$ 3,502
Beginning balance (in shares) at Mar. 31, 2020			100,362,973
Beginning balance at Mar. 31, 2020	241,948			892,510		(3,629)	(646,933)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Share-based compensation to employees	18,770			18,770
Proceeds from issuance of shares (in shares)			33,075
Proceeds from issuance of shares	1,667			1,667
Exercise of options and warrants and vested RSUs (in shares)			624,673
Exercise of options and vested RSUs	3,685			3,685
Other comprehensive income (loss), net of tax benefit	97					97
Net income (loss)	1,655						1,655
Ending balance (in shares) at Jun. 30, 2020			101,020,721
Ending balance at Jun. 30, 2020	267,822			916,632		(3,532)	(645,278)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Other comprehensive income (loss), tax benefit	0
Share-based compensation to employees	20,121			20,121
Exercise of options and warrants and vested RSUs (in shares)			707,606
Exercise of options and vested RSUs	9,514			9,514
Other comprehensive income (loss), net of tax benefit	296					296
Net income (loss)	9,284						9,284
Ending balance (in shares) at Sep. 30, 2020			101,728,327
Ending balance at Sep. 30, 2020	307,037			946,267		(3,236)	(635,994)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Other comprehensive income (loss), tax benefit	0
Beginning balance (in shares) at Dec. 31, 2020			102,334,276
Beginning balance at Dec. 31, 2020	476,526	(128,972)		1,111,435	(132,474)	(3,832)	(631,077)	3,502
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Share-based compensation to employees	18,863			18,863
Exercise of options and vested RSUs (in shares)			853,184
Exercise of options and vested RSUs	7,961			7,961
Other comprehensive income (loss), net of tax benefit	1,884					1,884
Net income (loss)	(4,128)						(4,128)
Ending balance (in shares) at Mar. 31, 2021			103,187,460
Ending balance at Mar. 31, 2021	372,134			1,005,785		(1,948)	(631,703)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Other comprehensive income (loss), tax benefit	0
Beginning balance (in shares) at Dec. 31, 2020			102,334,276
Beginning balance at Dec. 31, 2020	476,526	$ (128,972)		1,111,435	$ (132,474)	(3,832)	(631,077)	$ 3,502
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	(31,893)
Ending balance (in shares) at Sep. 30, 2021			103,817,566
Ending balance at Sep. 30, 2021	413,164			1,073,532		(900)	(659,468)
Beginning balance (in shares) at Mar. 31, 2021			103,187,460
Beginning balance at Mar. 31, 2021	372,134			1,005,785		(1,948)	(631,703)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Share-based compensation to employees	27,881			27,881
Exercise of options and vested RSUs (in shares)			436,487
Exercise of options and vested RSUs	8,695			8,695
Proceeds from issuance of shares (in shares)			17,291
Proceeds from issuance of shares	2,371			2,371
Other comprehensive income (loss), net of tax benefit	829					829
Net income (loss)	(14,641)						(14,641)
Ending balance (in shares) at Jun. 30, 2021			103,641,238
Ending balance at Jun. 30, 2021	397,269			1,044,732		(1,119)	(646,344)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Other comprehensive income (loss), tax benefit	0
Share-based compensation to employees	25,758			25,758
Exercise of options and vested RSUs (in shares)			176,328
Exercise of options and vested RSUs	3,042			3,042
Other comprehensive income (loss), net of tax benefit	219					219
Net income (loss)	(13,124)						(13,124)
Ending balance (in shares) at Sep. 30, 2021			103,817,566
Ending balance at Sep. 30, 2021	413,164			$ 1,073,532		$ (900)	$ (659,468)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Other comprehensive income (loss), tax benefit	$ 0