Statements of Changes in Stockholders' Equity - USD ($) shares in Thousands, $ in Thousands	Common Stock	Additional Paid-in Capital	Accumulated Deficit	Total
Beginning balance at Dec. 31, 2020	$ 191	$ 302,842	$ (277,540)	$ 25,493
Beginning balance, shares at Dec. 31, 2020	19,114
Share-based awards and options exercises	$ 11	1,581		1,592
Share-based awards and options exercises, shares	1,076
Issuance of common stock	$ 56	80,515		80,571
Issuance of common stock (in shares)	5,566
Share-based compensation expense		2,196		2,196
Net Loss			(7,881)	(7,881)
Ending balance at Mar. 31, 2021	$ 258	387,134	(285,421)	101,971
Ending balance, shares at Mar. 31, 2021	25,756
Beginning balance at Dec. 31, 2020	$ 191	302,842	(277,540)	25,493
Beginning balance, shares at Dec. 31, 2020	19,114
Net Loss				(15,406)
Ending balance at Jun. 30, 2021	$ 262	389,850	(292,946)	97,166
Ending balance, shares at Jun. 30, 2021	26,167
Beginning balance at Mar. 31, 2021	$ 258	387,134	(285,421)	101,971
Beginning balance, shares at Mar. 31, 2021	25,756
Share-based awards and options exercises	$ 4	707		711
Share-based awards and options exercises, shares	411
Share-based compensation expense		2,009		2,009
Net Loss			(7,525)	(7,525)
Ending balance at Jun. 30, 2021	$ 262	389,850	(292,946)	97,166
Ending balance, shares at Jun. 30, 2021	26,167
Beginning balance at Dec. 31, 2021	$ 264	393,644	(308,733)	85,175
Beginning balance, shares at Dec. 31, 2021	26,395
Share-based awards and options exercises	$ 3	6		9
Share-based awards and options exercises, shares	322
Share-based compensation expense		2,252		2,252
Net Loss			(10,838)	(10,838)
Ending balance at Mar. 31, 2022	$ 267	395,902	(319,571)	76,598
Ending balance, shares at Mar. 31, 2022	26,717
Beginning balance at Dec. 31, 2021	$ 264	393,644	(308,733)	85,175
Beginning balance, shares at Dec. 31, 2021	26,395
Net Loss				(21,260)
Ending balance at Jun. 30, 2022	$ 268	398,147	(329,993)	68,422
Ending balance, shares at Jun. 30, 2022	26,856
Beginning balance at Mar. 31, 2022	$ 267	395,902	(319,571)	76,598
Beginning balance, shares at Mar. 31, 2022	26,717
Share-based awards and options exercises	$ 1	42		43
Share-based awards and options exercises, shares	139
Share-based compensation expense		2,203		2,203
Net Loss			(10,422)	(10,422)
Ending balance at Jun. 30, 2022	$ 268	$ 398,147	$ (329,993)	$ 68,422
Ending balance, shares at Jun. 30, 2022	26,856