Condensed Statements of Stockholders’ Equity - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Accumulated Other Comprehensive Income(Loss)	Accumulated Deficit
Balance, beginning (in shares) at Dec. 31, 2020		42,196,296
Balance, beginning at Dec. 31, 2020	$ 191,216		$ 524,022		$ (332,806)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shares issued upon exercises of stock options (in shares)		91,737
Shares issued upon exercises of stock options	282		282
Shares issued upon vesting of restricted stock units (in shares)		38,000
Stock-based compensation	2,420		2,420
Net loss	(14,950)				(14,950)
Balance, ending (in shares) at Mar. 31, 2021		42,326,033
Balance, ending at Mar. 31, 2021	178,968		526,724		(347,756)
Balance, beginning (in shares) at Dec. 31, 2020		42,196,296
Balance, beginning at Dec. 31, 2020	$ 191,216		524,022		(332,806)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shares issued upon exercises of stock options (in shares)	116,861
Unrealized loss on available-for-sale securities	$ 0
Net loss	(30,079)
Balance, ending (in shares) at Jun. 30, 2021		42,419,129
Balance, ending at Jun. 30, 2021	167,071		529,956		(362,885)
Balance, beginning (in shares) at Mar. 31, 2021		42,326,033
Balance, beginning at Mar. 31, 2021	178,968		526,724		(347,756)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shares issued upon exercises of stock options (in shares)		25,124
Shares issued upon exercises of stock options	95		95
Issuance of shares under Employee Stock Purchase Plan (in shares)		22,972
Issuance of shares under Employee Stock Purchase Plan	219		219
Shares issued upon vesting of restricted stock units (in shares)		45,000
Stock-based compensation	2,918		2,918
Unrealized loss on available-for-sale securities	0
Net loss	(15,129)				(15,129)
Balance, ending (in shares) at Jun. 30, 2021		42,419,129
Balance, ending at Jun. 30, 2021	167,071		529,956		(362,885)
Balance, beginning (in shares) at Dec. 31, 2021		42,457,471
Balance, beginning at Dec. 31, 2021	142,864		536,362	$ 0	(393,498)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shares issued upon exercises of stock options (in shares)		36,500
Shares issued upon exercises of stock options	134		134
Stock-based compensation	2,446		2,446
Net loss	(15,351)				(15,351)
Balance, ending (in shares) at Mar. 31, 2022		42,493,971
Balance, ending at Mar. 31, 2022	130,093		538,942	0	(408,849)
Balance, beginning (in shares) at Dec. 31, 2021		42,457,471
Balance, beginning at Dec. 31, 2021	$ 142,864		536,362	0	(393,498)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shares issued upon exercises of stock options (in shares)	36,500
Unrealized loss on available-for-sale securities	$ (72)
Net loss	(31,039)
Balance, ending (in shares) at Jun. 30, 2022		42,579,852
Balance, ending at Jun. 30, 2022	116,708		541,317	(72)	(424,537)
Balance, beginning (in shares) at Mar. 31, 2022		42,493,971
Balance, beginning at Mar. 31, 2022	130,093		538,942	0	(408,849)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of shares under Employee Stock Purchase Plan (in shares)		75,881
Issuance of shares under Employee Stock Purchase Plan	63		63
Shares issued upon vesting of restricted stock units (in shares)		10,000
Stock-based compensation	2,312		2,312
Unrealized loss on available-for-sale securities	(72)			(72)
Net loss	(15,688)				(15,688)
Balance, ending (in shares) at Jun. 30, 2022		42,579,852
Balance, ending at Jun. 30, 2022	$ 116,708		$ 541,317	$ (72)	$ (424,537)