Condensed Consolidated Statements of Stockholders' Equity - USD ($) shares in Thousands, $ in Thousands	Common Stock Contractors Contractors or Consultants	Common Stock Employees	Common Stock	Additional Paid-in Capital Contractors Contractors or Consultants	Additional Paid-in Capital Employees	Additional Paid-in Capital Contractors or Consultants	Additional Paid-in Capital	Accumulated Deficit Contractors Contractors or Consultants	Accumulated Deficit Employees	Accumulated Deficit	Accumulated Other Comprehensive Income Contractors Contractors or Consultants	Accumulated Other Comprehensive Income Employees	Accumulated Other Comprehensive Income	Contractors Contractors or Consultants	Employees	Contractors or Consultants	Total
Balance at Dec. 31, 2020			$ 140,733				$ 49,234			$ (162,140)			$ 1,243				$ 29,070
Balance (in shares) at Dec. 31, 2020			26,003
Stock options issued	$ 0	$ 0		$ 9	$ 587			$ 0	$ 0		$ 0	$ 0		$ 9	$ 587
Net loss										(4,733)							(4,733)
Balance at Mar. 31, 2021			$ 140,733				49,830			(166,873)			1,243				24,933
Balance (in shares) at Mar. 31, 2021			26,003
Balance at Dec. 31, 2020			$ 140,733				49,234			(162,140)			1,243				29,070
Balance (in shares) at Dec. 31, 2020			26,003
Net loss																	(8,734)
Balance at Jun. 30, 2021			$ 140,780				51,132			(170,874)			1,243				22,281
Balance (in shares) at Jun. 30, 2021			26,007
Balance at Mar. 31, 2021			$ 140,733				49,830			(166,873)			1,243				24,933
Balance (in shares) at Mar. 31, 2021			26,003
Stock options issued					1,326										1,326
Exercise of stock options			$ 47				(24)										23
Exercise of stock options (in shares)			4
Net loss										(4,001)							(4,001)
Balance at Jun. 30, 2021			$ 140,780				51,132			(170,874)			1,243				22,281
Balance (in shares) at Jun. 30, 2021			26,007
Balance at Dec. 31, 2021			$ 140,801				53,214			(179,486)			1,243				15,772
Balance (in shares) at Dec. 31, 2021			26,014
Stock options issued	$ 0	$ 0		$ 34	399			$ 0	$ 0		$ 0	$ 0		$ 34	399
Exercise of stock options			$ 31				(16)										$ 15
Exercise of stock options (in shares)			26														26
Net loss										(3,696)							$ (3,696)
Balance at Mar. 31, 2022			$ 140,832				53,631			(183,182)			1,243				12,524
Balance (in shares) at Mar. 31, 2022			26,040
Balance at Dec. 31, 2021			$ 140,801				53,214			(179,486)			1,243				15,772
Balance (in shares) at Dec. 31, 2021			26,014
Net loss																	(8,768)
Balance at Jun. 30, 2022			$ 140,922				54,630			(188,254)			1,243				8,541
Balance (in shares) at Jun. 30, 2022			26,067
Balance at Mar. 31, 2022			$ 140,832				53,631			(183,182)			1,243				12,524
Balance (in shares) at Mar. 31, 2022			26,040
Stock options issued					$ 1,008	$ 35									$ 1,008	$ 35
Exercise of stock options			$ 90				(44)										$ 46
Exercise of stock options (in shares)			19														19
Restricted stock unit release (in shares)			8
Net loss										(5,072)							$ (5,072)
Balance at Jun. 30, 2022			$ 140,922				$ 54,630			$ (188,254)			$ 1,243				$ 8,541
Balance (in shares) at Jun. 30, 2022			26,067