Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Total	Common Stock [Member]	Additional Paid-In Capital [Member]	Accumulated Deficit [Member]
Balances at beginning at Dec. 31, 2019	$ 14,947	$ 45	$ 172,708	$ (157,806)
Balances at beginning (shares) at Dec. 31, 2019		44,658,054
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock-based compensation	1,500		1,500
Issuance of restricted stock units and option exercises under equity incentive plan	17		17
Issuance of restricted stock units and option exercises under equity incentive plan (shares)		109,154
Issuance of common stock	53,722	$ 35	53,687
Issuance of common stock (shares)		34,848,484
Net loss	(24,639)			(24,639)
Balances at ending at Dec. 31, 2020	45,547	$ 80	227,912	(182,445)
Balances at end (shares) at Dec. 31, 2020		79,615,692
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock-based compensation	3,276		3,276
Issuance of restricted stock units under equity incentive plan (shares)		307,690
Tax withholding payments for net share-settled equity awards	(120)		(120)
Tax withholding payments for net share-settled equity awards (shares)		(59,072)
Net loss	(30,910)			(30,910)
Balances at ending at Dec. 31, 2021	$ 17,793	$ 80	$ 231,068	$ (213,355)
Balances at end (shares) at Dec. 31, 2021		79,864,310