Consolidated Statements of Shareholders' Equity - USD ($) $ in Thousands	Total	Ordinary Shares	Additional Paid-in Capital	Accumulated Other Comprehensive Income (loss)	Accumulated Deficit
Balance at Dec. 31, 2020	$ 178,434	$ 12,507	$ 771,194	$ 373	$ (605,640)
Balance, Shares at Dec. 31, 2020		98,283,603
Share-based compensation expense	22,536		22,536
Exercise of share options	2,739	$ 224	2,515
Exercise of share options, Shares		1,727,254
Issuance of ESPP shares	564	$ 30	534
Issuance of ESPP shares, Shares		232,340
Vesting of restricted share units, net of shares withheld for taxes	(392)	$ 9	(401)
Vesting of restricted share units, net of shares withheld for taxes, shares		64,647
Sale of voting and non-voting ordinary shares, net of issuance costs	143,645	$ 3,310	140,335
Sale of voting and non-voting ordinary shares, net of issuance costs, Shares		24,115,755
Ordinary shares issued as part of consulting agreement		$ 3	(3)
Ordinary shares issued as part of consulting agreement, Shares		22,758
Ordinary shares issued as part of collaboration agreement	4,135	$ 170	3,965
Ordinary shares issued as part of collaboration agreement, Shares		1,227,738
Foreign currency translation	3,124			3,124
Unrealized loss on marketable debt securities	(251)			(251)
Net loss	(144,584)				(144,584)
Balance at Dec. 31, 2021	209,950	$ 16,253	940,675	3,246	(750,224)
Balance, Shares at Dec. 31, 2021		125,674,095
Share-based compensation expense	16,010		16,010
Exercise of share options	$ 1	$ 91	(90)
Exercise of share options, Shares	699,234	699,234
Issuance of ESPP shares	$ 211	$ 72	139
Issuance of ESPP shares, Shares		544,442
Vesting of restricted share units, net of shares withheld for taxes	(19)	$ 3	(22)
Vesting of restricted share units, net of shares withheld for taxes, shares		24,202
Ordinary shares issued as part of consulting agreement	(1)		(1)
Ordinary shares issued as part of consulting agreement, Shares		5,252
Foreign currency translation	22,838			22,838
Unrealized loss on marketable debt securities	(66)			(66)
Net loss	(150,660)				(150,660)
Balance at Dec. 31, 2022	$ 98,264	$ 16,419	$ 956,711	$ 26,018	$ (900,884)
Balance, Shares at Dec. 31, 2022		126,947,225