Statements of Convertible Preferred Stock and Stockholders' Deficit - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Accumulated Other Comprehensive Loss	Accumulated Deficit
Convertible preferred stock, beginning balance (in shares) at Dec. 31, 2017	0
Convertible preferred stock, beginning balance at Dec. 31, 2017	$ 0
Increase (Decrease) in Temporary Equity [Roll Forward]
Issuance of Series A convertible preferred stock, net of issuance costs (in shares)	7,806,977
Issuance of Series A convertible preferred stock, net of issuance costs	$ 17,985
Convertible preferred stock, ending balance (in shares) at Dec. 31, 2018	7,806,977
Convertible preferred stock, ending balance at Dec. 31, 2018	$ 17,985
Common stock, beginning balance (in shares) at Dec. 31, 2017		4,844,551
Beginning balance at Dec. 31, 2017	(610)	$ 5	$ 9	$ 0	$ (624)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Proceeds from common stockholder	4		4
Issuance of common stock upon vesting and exercise of options and vesting of restricted stock (in shares)		121,676
Issuance of common stock upon vesting and exercise of options and vesting of restricted stock	1		1
Stock-based compensation expense	30		30
Net unrealized loss on available-for-sale securities	0
Net loss	(6,721)				(6,721)
Common stock, ending balance (in shares) at Dec. 31, 2018		4,966,227
Beginning balance at Dec. 31, 2018	$ (7,296)	$ 5	44	0	(7,345)
Increase (Decrease) in Temporary Equity [Roll Forward]
Issuance of Series A convertible preferred stock, net of issuance costs (in shares)	13,697,916
Issuance of Series A convertible preferred stock, net of issuance costs	$ 104,922
Convertible preferred stock, ending balance (in shares) at Dec. 31, 2019	21,504,893
Convertible preferred stock, ending balance at Dec. 31, 2019	$ 122,907
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock upon vesting and exercise of options and vesting of restricted stock (in shares)		694,164
Issuance of common stock upon vesting and exercise of options and vesting of restricted stock	115	$ 1	114
Stock-based compensation expense	113		113
Net unrealized loss on available-for-sale securities	(18)			(18)
Net loss	(16,117)				(16,117)
Common stock, ending balance (in shares) at Dec. 31, 2019		5,660,391
Beginning balance at Dec. 31, 2019	$ (23,203)	$ 6	271	(18)	(23,462)
Convertible preferred stock, ending balance (in shares) at Dec. 31, 2020	0
Increase (Decrease) in Temporary Equity [Roll Forward]
Conversion of preferred stock into common stock (in shares)	(21,504,893)
Conversion of preferred stock into common stock	$ (122,907)
Convertible preferred stock, ending balance at Dec. 31, 2020	0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock upon vesting and exercise of options and vesting of restricted stock (in shares)		795,026
Issuance of common stock upon vesting and exercise of options and vesting of restricted stock	645		645
Stock-based compensation expense	3,753		3,753
Net unrealized loss on available-for-sale securities	(1)			(1)
Issuance of common stock upon initial public offering, net of issuance costs of $23,775 (in shares)		15,131,579
Issuance of common stock upon initial public offering, net of commission and issuance costs of $23,775	263,725	$ 15	263,710
Conversion of preferred stock into common stock (in shares)		22,687,625
Conversion of preferred stock into common stock	122,907	$ 23	122,884
Issuance of common stock upon conversion of convertible notes and change in fair value of convertible notes at time of conversion (in shares)	186,137	$ 10	186,127
Issuance of common stock upon conversion of convertible notes		9,799,280
Net loss	(88,444)				(88,444)
Common stock, ending balance (in shares) at Dec. 31, 2020		54,073,901
Beginning balance at Dec. 31, 2020	$ 465,519	$ 54	$ 577,390	$ (19)	$ (111,906)