Consolidated Statements of Changes in Stockholders' Equity - USD ($) $ in Thousands		Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Accumulated Deficit [Member]	Accumulated Other Comprehensive Income (Loss) [Member]
Beginning balances at Dec. 31, 2020		$ 64,383	$ 55	$ 320,893	$ (257,507)	$ 942
Beginning balance, shares at Dec. 31, 2020			54,152,955
Issuance of common stock and pre-funded warrants in public offering, net of offering costs	[1]	122,231	$ 57	122,174
Issuance of common stock and pre-funded warrants in public offering, net of offering costs,shares	[1]		57,479,978
Repurchase of outstanding pre-funded warrants		(3,909)		(3,909)
Issuance of common stock upon exercise of stock warrants, net		2,546	$ 2	2,544
Issuance of common stock upon exercise of stock warrants, net, shares			1,737,450
Issuance of common stock upon exercise of stock options		16	$ 1	15
Issuance of common stock upon exercise of stock options, shares			285,576
Issuance of common stock for settlement of RSUs			$ 1	(1)
Issuance of common stock for settlement of RSUs, shares			443,897
Repurchase of shares for minimum tax withholdings		(78)		(78)
Repurchase of shares for minimum tax withholdings,shares			(62,964)
Stock-based compensation		3,260		3,260
Foreign exchange translation adjustment		(887)				(887)
Unrealized gain (loss) on short-term investments		(50)				(50)
Net loss		(43,014)			(43,014)
Ending balance at Dec. 31, 2021		$ 144,498	$ 116	444,898	(300,521)	5
Ending balance, shares at Dec. 31, 2021		114,036,892	114,036,892
Issuance of common stock upon exercise of stock options		$ 2		2
Issuance of common stock upon exercise of stock options, shares		2,344	2,344
Issuance of common stock for settlement of RSUs, shares		8,672	9,125
Repurchase of shares for minimum tax withholdings		$ (3)		(3)
Repurchase of shares for minimum tax withholdings,shares			(2,016)
Stock-based compensation		2,041		2,041
Foreign exchange translation adjustment		(648)				(648)
Unrealized gain (loss) on short-term investments		38				38
Net loss		(38,150)			(38,150)
Ending balance at Dec. 31, 2022		$ 107,778	$ 116	$ 446,938	$ (338,671)	$ (605)
Ending balance, shares at Dec. 31, 2022		114,046,345	114,046,345

[1] As discussed in Note 9. Stockholders’ Equity, the Company sold (i) an aggregate of 57,479,978 shares of the Company’s common stock, par value $0.001 per share and (ii) pre-funded warrants to purchase an aggregate of 32,175,172 shares of the Company's common stock at an exercise price, equal to the par value, of $0.001 per share.