CONDENSED CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS' EQUITY - USD ($) $ in Thousands	Total	Common stock	Additional paid-in capital	Accumulated deficit
Beginning balance (shares) at Dec. 31, 2020		43,205,221
Beginning balance at Dec. 31, 2020	$ 37,493	$ 4	$ 603,685	$ (566,196)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	(20,550)			(20,550)
Exercise of options, vesting of restricted stock units and shares issued under employee stock purchase plan (in shares)		129,102
Exercise of options, vesting of restricted stock units and shares issued under employee stock purchase plan	388		388
Stock-based compensation	2,442		2,442
Issuance of common stock, net of issuance costs (in shares)		8,052,273
Issuance of common stock, net of issuance costs	73,128	$ 1	73,127
Ending balance (shares) at Mar. 31, 2021		51,386,596
Ending balance at Mar. 31, 2021	$ 92,901	$ 5	679,642	(586,746)
Beginning balance (shares) at Dec. 31, 2021	53,577,744	53,577,744
Beginning balance at Dec. 31, 2021	$ 48,636	$ 5	688,156	(639,525)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	4,670			4,670
Stock-based compensation	893		893
Vesting of restricted stock units, net of witholding tax (in shares)		75,297
Vesting of restricted stock units, net of withholding tax	$ (25)		(25)
Issuance of commitment shares (in shares)	1,667,593
Issuance of common stock, net of issuance costs (in shares)		2,587,855
Issuance of common stock, net of issuance costs	$ 1,557	$ 1	1,556
Ending balance (shares) at Mar. 31, 2022	57,908,489	57,908,489
Ending balance at Mar. 31, 2022	$ 55,731	$ 6	$ 690,580	$ (634,855)