Condensed Consolidated Statements of Stockholders' Equity (Unaudited) - USD ($) $ in Thousands	Total	Common Stock [Member]	Additional Paid-In Capital [Member]	Accumulated Other Comprehensive (Loss) Income [Member]	Accumulated Deficit [Member]
Balance at Dec. 31, 2020	$ 95,035	$ 34	$ 401,509	$ (8)	$ (306,500)
Balance, beginning of period, Shares at Dec. 31, 2020		33,878,486
Issuance of common stock upon exercise of stock options	166		166
Issuance of common stock upon exercise of stock options, Shares		19,150
Vesting of common stock issued under Product Development Agreement	53		53
Issuance of common stock upon ESPP purchase	136		136
Issuance of common stock upon ESPP purchase, Shares		19,928
Issuance of common stock upon release of restricted stock units, Shares		33,750
Stock-based compensation expense	1,549		1,549
Unrealized (loss) gain on available-for-sale debt securities, net	3			3
Net (loss) income	29,248				29,248
Balance at Mar. 31, 2021	126,190	$ 34	403,413	(5)	(277,252)
Balance, end of period, Shares at Mar. 31, 2021		33,951,314
Balance at Dec. 31, 2021	72,399	$ 35	412,930	(149)	(340,417)
Balance, beginning of period, Shares at Dec. 31, 2021		34,568,821
Issuance of common stock upon offering at-the-market, net of commissions	45,610	$ 6	45,604
Issuance of common stock upon offering at-the-market, net of commissions, shares		5,841,786
Issuance of common stock upon exercise of stock options	$ 144		144
Issuance of common stock upon exercise of stock options, Shares	15,995	15,995
Vesting of common stock issued under Product Development Agreement	$ 19		19
Issuance of common stock upon ESPP purchase	64		64
Issuance of common stock upon ESPP purchase, Shares		18,130
Issuance of common stock upon release of restricted stock units, Shares		85,106
Stock-based compensation expense	2,047		2,047
Unrealized (loss) gain on available-for-sale debt securities, net	(373)			(373)
Net (loss) income	(22,643)				(22,643)
Balance at Mar. 31, 2022	$ 97,267	$ 41	$ 460,808	$ (522)	$ (363,060)
Balance, end of period, Shares at Mar. 31, 2022		40,529,838