CONSOLIDATED STATEMENTS OF CHANGES IN SHAREHOLDERS' EQUITY - USD ($) $ in Thousands	Total	Ordinary shares	Additional paid-in capital	Accumulated other comprehensive loss	Retained earnings (accumulated deficit)
Beginning balance at Dec. 31, 2018	$ 112,259		$ 757,314	$ (1,400)	$ (643,655)
Beginning balance (in shares) at Dec. 31, 2018		93,254,185
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Share-based compensation to employees	9,649		9,649
Exercise of options and vested RSUs	16,978		16,978
Exercise of options and warrants and vested RSUs (in shares)		2,438,612
Other comprehensive income (loss), net of tax benefit	(342)			(342)
Net income (loss)	(12,150)				(12,150)
Ending balance at Mar. 31, 2019	126,394		783,941	(1,742)	(655,805)
Ending balance (in shares) at Mar. 31, 2019		95,692,797
Beginning balance at Dec. 31, 2018	112,259		757,314	(1,400)	(643,655)
Beginning balance (in shares) at Dec. 31, 2018		93,254,185
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	(13,420)
Ending balance at Jun. 30, 2019	158,906		818,338	(2,357)	(657,075)
Ending balance (in shares) at Jun. 30, 2019		97,858,876
Beginning balance at Dec. 31, 2018	112,259		757,314	(1,400)	(643,655)
Beginning balance (in shares) at Dec. 31, 2018		93,254,185
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	(7,230)
Ending balance at Dec. 31, 2019	217,790		871,442	(2,767)	(650,885)
Ending balance (in shares) at Dec. 31, 2019		99,528,435
Beginning balance at Mar. 31, 2019	126,394		783,941	(1,742)	(655,805)
Beginning balance (in shares) at Mar. 31, 2019		95,692,797
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Share-based compensation to employees	13,732		13,732
Proceeds from issuance of shares	1,208		1,208
Proceeds from issuance of shares (in shares)		43,421
Exercise of options and vested RSUs	19,457		19,457
Exercise of options and warrants and vested RSUs (in shares)		2,122,658
Other comprehensive income (loss), net of tax benefit	(615)			(615)
Net income (loss)	(1,270)				(1,270)
Ending balance at Jun. 30, 2019	158,906		818,338	(2,357)	(657,075)
Ending balance (in shares) at Jun. 30, 2019		97,858,876
Beginning balance at Dec. 31, 2019	217,790		871,442	(2,767)	(650,885)
Beginning balance (in shares) at Dec. 31, 2019		99,528,435
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Share-based compensation to employees	16,557		16,557
Exercise of options and vested RSUs	4,511		4,511
Exercise of options and warrants and vested RSUs (in shares)		834,538
Other comprehensive income (loss), net of tax benefit	(862)			(862)
Net income (loss)	3,952				3,952
Ending balance at Mar. 31, 2020	241,948		892,510	(3,629)	(646,933)
Ending balance (in shares) at Mar. 31, 2020		100,362,973
Beginning balance at Dec. 31, 2019	217,790		871,442	(2,767)	(650,885)
Beginning balance (in shares) at Dec. 31, 2019		99,528,435
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	5,607
Ending balance at Jun. 30, 2020	267,822		916,632	(3,532)	(645,278)
Ending balance (in shares) at Jun. 30, 2020		101,020,721
Beginning balance at Mar. 31, 2020	241,948		892,510	(3,629)	(646,933)
Beginning balance (in shares) at Mar. 31, 2020		100,362,973
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Share-based compensation to employees	18,770		18,770
Proceeds from issuance of shares	1,667		1,667
Proceeds from issuance of shares (in shares)		33,075
Exercise of options and vested RSUs	3,685		3,685
Exercise of options and warrants and vested RSUs (in shares)		624,673
Other comprehensive income (loss), net of tax benefit	97			97
Net income (loss)	1,655				1,655
Ending balance at Jun. 30, 2020	$ 267,822		$ 916,632	$ (3,532)	$ (645,278)
Ending balance (in shares) at Jun. 30, 2020		101,020,721