CONDENSED CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($) $ in Thousands	Total	Preferred Stock	Common Stock	Additional Paid-in Capital	Accumulated Deficit
Beginning balance (in shares) at Dec. 31, 2019		0	17,130,907
Beginning balance at Dec. 31, 2019	$ 85,113	$ 0	$ 17	$ 137,308	$ (52,212)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock compensation expense	1,577			1,577
Exercise of common stock options (in shares)			32,602
Exercise of common stock options	71			71
Issuance of common stock under the employee stock purchase plan (in shares)			39,987
Issuance of common stock under the employee stock purchase plan	603			603
Net income (loss)	570				570
Ending balance (in shares) at Mar. 31, 2020		0	17,203,496
Ending balance at Mar. 31, 2020	87,934	$ 0	$ 17	139,559	(51,642)
Beginning balance (in shares) at Dec. 31, 2019		0	17,130,907
Beginning balance at Dec. 31, 2019	85,113	$ 0	$ 17	137,308	(52,212)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	(806)
Ending balance (in shares) at Jun. 30, 2020		0	19,373,869
Ending balance at Jun. 30, 2020	157,622	$ 0	$ 19	210,621	(53,018)
Beginning balance (in shares) at Mar. 31, 2020		0	17,203,496
Beginning balance at Mar. 31, 2020	87,934	$ 0	$ 17	139,559	(51,642)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock compensation expense	1,653			1,653
Exercise of common stock options (in shares)			170,373
Exercise of common stock options	330			330
Public offering of common stock, net of underwriting discounts, commissions and offering costs (in shares)			2,000,000
Public offering of common stock, net of underwriting discounts, commissions and offering costs	69,081		$ 2	69,079
Net income (loss)	(1,376)				(1,376)
Ending balance (in shares) at Jun. 30, 2020		0	19,373,869
Ending balance at Jun. 30, 2020	157,622	$ 0	$ 19	210,621	(53,018)
Beginning balance (in shares) at Dec. 31, 2020		0	24,812,487
Beginning balance at Dec. 31, 2020	415,691	$ 0	$ 25	478,162	(62,496)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock compensation expense	4,913			4,913
Exercise of common stock options (in shares)			171,315
Exercise of common stock options	991			991
Issuance of common stock under the employee stock purchase plan (in shares)			70,711
Issuance of common stock under the employee stock purchase plan	1,233			1,233
Public offering of common stock, adjustment to offering costs	39			39
Net income (loss)	(4,280)				(4,280)
Ending balance (in shares) at Mar. 31, 2021		0	25,054,513
Ending balance at Mar. 31, 2021	418,587	$ 0	$ 25	485,338	(66,776)
Beginning balance (in shares) at Dec. 31, 2020		0	24,812,487
Beginning balance at Dec. 31, 2020	$ 415,691	$ 0	$ 25	478,162	(62,496)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Exercise of common stock options (in shares)	282,685
Net income (loss)	$ (13,071)
Ending balance (in shares) at Jun. 30, 2021		0	25,164,053
Ending balance at Jun. 30, 2021	415,916	$ 0	$ 25	491,458	(75,567)
Beginning balance (in shares) at Mar. 31, 2021		0	25,054,513
Beginning balance at Mar. 31, 2021	418,587	$ 0	$ 25	485,338	(66,776)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock compensation expense	4,766			4,766
Exercise of common stock options (in shares)			109,540
Exercise of common stock options	1,354			1,354
Net income (loss)	(8,791)				(8,791)
Ending balance (in shares) at Jun. 30, 2021		0	25,164,053
Ending balance at Jun. 30, 2021	$ 415,916	$ 0	$ 25	$ 491,458	$ (75,567)