Condensed Consolidated Statements of Changes in Stockholders' Equity (Unaudited) - USD ($) $ in Thousands		Total	Registered Direct Offering of Common Stock and Pre-funded Warrants [Member]	Common Stock [Member]	Common Stock [Member] Registered Direct Offering of Common Stock and Pre-funded Warrants [Member]	Additional Paid-in Capital [Member]	Additional Paid-in Capital [Member] Registered Direct Offering of Common Stock and Pre-funded Warrants [Member]	Accumulated Deficit [Member]	Accumulated Other Comprehensive Income (Loss) [Member]
Beginning balances at Dec. 31, 2021		$ 144,498		$ 116		$ 444,898		$ (300,521)	$ 5
Beginning balance, shares at Dec. 31, 2021				114,036,892
Issuance of common stock for settlement of RSUs, shares				3,688
Repurchase of shares for minimum tax withholdings		(1)				(1)
Repurchase of shares for minimum tax withholdings, shares				(720)
Stock-based compensation		574				574
Foreign exchange translation adjustment		(208)							(208)
Unrealized gain (loss) on short-term investments		(88)							(88)
Net loss		(8,300)						(8,300)
Ending balances at Mar. 31, 2022		136,475		$ 116		445,471		(308,821)	(291)
Ending balance, shares at Mar. 31, 2022				114,039,860
Beginning balances at Dec. 31, 2021		144,498		$ 116		444,898		(300,521)	5
Beginning balance, shares at Dec. 31, 2021				114,036,892
Foreign exchange translation adjustment		(1,621)
Unrealized gain (loss) on short-term investments		9
Net loss		(27,850)
Ending balances at Sep. 30, 2022		116,514		$ 116		446,376		(328,371)	(1,607)
Ending balance, shares at Sep. 30, 2022				114,042,642
Beginning balances at Mar. 31, 2022		136,475		$ 116		445,471		(308,821)	(291)
Beginning balance, shares at Mar. 31, 2022				114,039,860
Issuance of common stock for settlement of RSUs, shares				1,812
Repurchase of shares for minimum tax withholdings, shares				(401)
Stock-based compensation		456				456
Foreign exchange translation adjustment		(745)							(745)
Unrealized gain (loss) on short-term investments		20							20
Net loss		(9,164)						(9,164)
Ending balances at Jun. 30, 2022		127,042		$ 116		445,927		(317,985)	(1,016)
Ending balance, shares at Jun. 30, 2022				114,041,271
Issuance of common stock for settlement of RSUs, shares				1,813
Repurchase of shares for minimum tax withholdings		(1)				(1)
Repurchase of shares for minimum tax withholdings, shares				(442)
Stock-based compensation		450				450
Foreign exchange translation adjustment		(668)							(668)
Unrealized gain (loss) on short-term investments		77							77
Net loss		(10,386)						(10,386)
Ending balances at Sep. 30, 2022		116,514		$ 116		446,376		(328,371)	(1,607)
Ending balance, shares at Sep. 30, 2022				114,042,642
Beginning balances at Dec. 31, 2022		$ 107,778		$ 116		446,938		(338,671)	(605)
Beginning balance, shares at Dec. 31, 2022		114,046,345		114,046,345
Issuance of common stock upon exercise of stock options		$ 27				27
Issuance of common stock upon exercise of stock options, shares				17,129
Issuance of common stock for settlement of RSUs, shares				1,813
Repurchase of shares for minimum tax withholdings		(1)				(1)
Repurchase of shares for minimum tax withholdings, shares				(551)
Stock-based compensation		864				864
Foreign exchange translation adjustment		130							130
Unrealized gain (loss) on short-term investments		14							14
Net loss		(10,557)						(10,557)
Ending balances at Mar. 31, 2023		98,255		$ 116		447,828		(349,228)	(461)
Ending balance, shares at Mar. 31, 2023				114,064,736
Beginning balances at Dec. 31, 2022		$ 107,778		$ 116		446,938		(338,671)	(605)
Beginning balance, shares at Dec. 31, 2022		114,046,345		114,046,345
Issuance of common stock upon exercise of stock options, shares		171,067
Issuance of common stock for settlement of RSUs, shares		179,419
Foreign exchange translation adjustment		$ (286)
Unrealized gain (loss) on short-term investments		(51)
Net loss		(38,599)
Ending balances at Sep. 30, 2023		$ 146,544		$ 137		524,619		(377,270)	(942)
Ending balance, shares at Sep. 30, 2023		135,339,836		135,339,836
Beginning balances at Mar. 31, 2023		$ 98,255		$ 116		447,828		(349,228)	(461)
Beginning balance, shares at Mar. 31, 2023				114,064,736
Issuance of common stock upon exercise of stock options		103				103
Issuance of common stock upon exercise of stock options, shares				84,375
Issuance of common stock for settlement of RSUs, shares				1,812
Repurchase of shares for minimum tax withholdings, shares				(468)
Stock-based compensation		958				958
Foreign exchange translation adjustment		(98)							(98)
Unrealized gain (loss) on short-term investments		(60)							(60)
Net loss		(11,443)						(11,443)
Ending balances at Jun. 30, 2023		87,715		$ 116		448,889		(360,671)	(619)
Ending balance, shares at Jun. 30, 2023				114,150,455
Issuance of common stock upon exercise of stock options		64				64
Issuance of common stock upon exercise of stock options, shares				63,610
Issuance of common stock and pre-funded warrants in registered direct offering, net of offering costs	[1]		$ 74,874		$ 21		$ 74,853
Issuance of common stock and pre-funded warrants in registered direct offering, net of offering costs, shares	[1]				21,000,000
Issuance of common stock for settlement of RSUs, shares				176,813
Repurchase of shares for minimum tax withholdings		(182)				(182)
Repurchase of shares for minimum tax withholdings, shares				(51,042)
Stock-based compensation		995				995
Foreign exchange translation adjustment		(318)							(318)
Unrealized gain (loss) on short-term investments		(5)							(5)
Net loss		(16,599)						(16,599)
Ending balances at Sep. 30, 2023		$ 146,544		$ 137		$ 524,619		$ (377,270)	$ (942)
Ending balance, shares at Sep. 30, 2023		135,339,836		135,339,836

[1] As discussed in Note 8. Stockholders’ Equity, the Company sold (i) an aggregate of 21,000,000 shares of the Company’s common stock, par value $0.001 per share and (ii) pre-funded warrants to purchase an aggregate of 5,666,667 shares of the Company's common stock at an exercise price, equal to the par value, of $0.001 per share.