Consolidated Statements of Shareholders' Equity (Unaudited) - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-in Capital	AOCI Attributable to Parent	Accumulated Deficit
Balance at Dec. 31, 2020	$ 78,911	$ 30	$ 232,159	$ 7	$ (153,285)
Balance, Shares at Dec. 31, 2020		30,351,366
Issuance of common stock from ATM offering, net ofsales agent commission and fees	10,357	$ 1	10,356
Issuance of common stock from ATM offering, net of sales agent commission and fees, Shares		907,700
Stock-based compensation	5,290		5,290
Exercise of stock options	1,228		1,228
Exercise of stock options, Shares		193,355
Issuance of common stock upon exercise of warrants, net, Shares		8,048
Restricted stock awards released, shares		16,666
Repurchase of restricted stock awards	(85)		(85)
Repurchase of restricted stock awards, Shares		(6,919)
Unrealized losses from available-for-sale securities	(7)			(7)
Net loss	(22,784)				(22,784)
Balance at Jun. 30, 2021	72,910	$ 31	248,948	0	(176,069)
Balance, Shares at Jun. 30, 2021		31,470,216
Balance at Mar. 31, 2021	69,669	$ 31	235,428	0	(165,790)
Balance, Shares at Mar. 31, 2021		30,499,803
Issuance of common stock from ATM offering, net ofsales agent commission and fees	10,356		10,356
Issuance of common stock from ATM offering, net of sales agent commission and fees, Shares		907,700
Stock-based compensation	2,854		2,854
Exercise of stock options	310		310
Exercise of stock options, Shares		62,713
Net loss	(10,279)				(10,279)
Balance at Jun. 30, 2021	72,910	$ 31	248,948	0	(176,069)
Balance, Shares at Jun. 30, 2021		31,470,216
Balance at Dec. 31, 2021	65,492	$ 32	262,906	0	(197,446)
Balance, Shares at Dec. 31, 2021		32,202,496
Issuance of common stock from ATM offering, net ofsales agent commission and fees	16,598	$ 3	16,595
Issuance of common stock from ATM offering, net of sales agent commission and fees, Shares		3,117,220
Stock-based compensation	$ 5,320		5,320
Exercise of stock options, Shares	0
Restricted stock awards released, shares		91,668
Restricted stock awards withheld at vesting to cover taxes, Shares		(39,190)
Restricted stock awards withheld at vesting to cover taxes, Amount	$ (191)		(191)
Net loss	(27,463)				(27,463)
Balance at Jun. 30, 2022	59,756	$ 35	284,630	0	(224,909)
Balance, Shares at Jun. 30, 2022		35,381,743
Balance at Mar. 31, 2022	64,673	$ 34	276,340	0	(211,701)
Balance, Shares at Mar. 31, 2022		34,174,800
Issuance of common stock from ATM offering, net ofsales agent commission and fees	5,982	$ 1	5,981
Issuance of common stock from ATM offering, net of sales agent commission and fees, Shares		1,197,394
Stock-based compensation	2,309		2,309
Issuance of common stock upon exercise of warrants, net, Shares		9,549
Net loss	(13,208)				(13,208)
Balance at Jun. 30, 2022	$ 59,756	$ 35	$ 284,630	$ 0	$ (224,909)
Balance, Shares at Jun. 30, 2022		35,381,743