Condensed Statements of Stockholders' Equity - USD ($) $ in Thousands	Common Stock	Additional Paid-In Capital	Accumulated Deficit	Total
Balance at Dec. 31, 2020	$ 2	$ 174,584	$ (157,174)	$ 17,412
Balance (in shares) at Dec. 31, 2020	19,031,556
Increase (Decrease) in Stockholders' Equity
Exercise of stock options		144		144
Exercise of stock options (in shares)	54,077
Issuance of common stock under stock incentive plans		364		364
Issuance of common stock under stock incentive plans (in shares)	136,709
Stock-based compensation expense		743		743
Net income (loss)			(460)	(460)
Balance at Mar. 31, 2021	$ 2	175,835	(157,634)	18,203
Balance (in shares) at Mar. 31, 2021	19,222,342
Balance at Dec. 31, 2020	$ 2	174,584	(157,174)	17,412
Balance (in shares) at Dec. 31, 2020	19,031,556
Increase (Decrease) in Stockholders' Equity
Net income (loss)				(204)
Balance at Jun. 30, 2021	$ 2	176,688	(157,378)	19,312
Balance (in shares) at Jun. 30, 2021	19,435,274
Balance at Mar. 31, 2021	$ 2	175,835	(157,634)	18,203
Balance (in shares) at Mar. 31, 2021	19,222,342
Increase (Decrease) in Stockholders' Equity
Exercise of stock options		57		57
Exercise of stock options (in shares)	23,280
Issuance of common stock under stock incentive plans		92		92
Issuance of common stock under stock incentive plans (in shares)	189,652
Stock-based compensation expense		704		704
Net income (loss)			256	256
Balance at Jun. 30, 2021	$ 2	176,688	(157,378)	19,312
Balance (in shares) at Jun. 30, 2021	19,435,274
Balance at Dec. 31, 2021	$ 2	180,067	(152,831)	27,238
Balance (in shares) at Dec. 31, 2021	19,858,460
Increase (Decrease) in Stockholders' Equity
Exercise of stock options		69		69
Exercise of stock options (in shares)	15,830
Issuance of common stock under stock incentive plans (in shares)	96,496
Stock-based compensation expense		824		824
Net income (loss)			1,935	1,935
Balance at Mar. 31, 2022	$ 2	180,960	(150,896)	30,066
Balance (in shares) at Mar. 31, 2022	19,970,786
Balance at Dec. 31, 2021	$ 2	180,067	(152,831)	$ 27,238
Balance (in shares) at Dec. 31, 2021	19,858,460
Increase (Decrease) in Stockholders' Equity
Exercise of stock options (in shares)				33,961
Net income (loss)				$ 3,606
Balance at Jun. 30, 2022	$ 2	182,488	(149,225)	33,265
Balance (in shares) at Jun. 30, 2022	20,137,520
Balance at Mar. 31, 2022	$ 2	180,960	(150,896)	30,066
Balance (in shares) at Mar. 31, 2022	19,970,786
Increase (Decrease) in Stockholders' Equity
Exercise of stock options		50		50
Exercise of stock options (in shares)	18,131
Issuance of common stock under stock incentive plans		167		167
Issuance of common stock under stock incentive plans (in shares)	148,603
Stock-based compensation expense		1,311		1,311
Net income (loss)			1,671	1,671
Balance at Jun. 30, 2022	$ 2	$ 182,488	$ (149,225)	$ 33,265
Balance (in shares) at Jun. 30, 2022	20,137,520