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)	(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
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