Consolidated Statements of Convertible Preferred Stock, Redeemable Common Stock and Stockholders' Equity (Deficit) - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-In Capital	Accumulated Other Comprehensive Income (Loss)	Accumulated Deficit	Convertible Preferred Stock	Redeemable Common Stock
Beginning balance, convertible preferred stock (in share) at Dec. 31, 2017						38,018,968	107,371
Beginning balance, convertible preferred stock at Dec. 31, 2017						$ 60,903	$ 734
Increase (Decrease) in Temporary Equity [Roll Forward]
Repurchase of Series Seed convertible preferred stock, net of issuance cost of $11,000 (in shares)						(598,975)
Repurchase of Series Seed convertible preferred stock, net of issuance costs of $11 thousand	$ (22)				$ (22)	$ (517)
Issuance cost of convertible preferred stock, net of issuance cost (in shares)						2,659,574
Issuance costs of convertible preferred stock, net of issuance costs	0					$ 4,289
Conversion of redeemable common stock into common stock	0
Ending balance, convertible preferred stock (in shares) at Dec. 31, 2018						40,079,567	107,371
Ending balance, convertible preferred stock at Dec. 31, 2018						$ 64,675	$ 734
Beginning balance (in shares) at Dec. 31, 2017		350,607
Beginning balance at Dec. 31, 2017	(44,545)	$ 0	$ 1,385	$ 0	(45,930)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Exercise of stock options (in shares)		1,045
Exercise of stock options	7		7
APIC, Share-based Payment Arrangement, Increase for Cost Recognition	759		759
Net loss	(33,285)				(33,285)
Ending balance (in shares) at Dec. 31, 2018		351,652
Ending balance at Dec. 31, 2018	(77,086)	$ 0	2,151	0	(79,237)
Increase (Decrease) in Temporary Equity [Roll Forward]
Repurchase of Series Seed convertible preferred stock, net of issuance costs of $11 thousand	0
Conversion of redeemable common stock into common stock (in shares)		107,364					(107,371)
Conversion of redeemable common stock into common stock	734		734				$ (734)
Conversion of convertible preferred shares into common stock (in shares)		3,808,430				(40,079,567)
Conversion of convertible preferred shares into common stock	64,675	$ 4	64,671			$ (64,675)
Ending balance, convertible preferred stock (in shares) at Dec. 31, 2019						0	0
Ending balance, convertible preferred stock at Dec. 31, 2019						$ 0	$ 0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Exchange of common stock in connection with Merger (in shares)		2,440,582
Exchange of common stock in connection with Merger	45,541	$ 2	45,539
Fair value of replacement equity awards	817		817
Reclassification of warrant liability to permanent equity	5,235		5,235
Issuance of common stock and prefunded warrants for the purchase of common stock, net of issuance costs of $11.5 million (in shares)		9,336,667
Issuance of common stock and prefunded warrants for the purchase of common stock, net of issuance costs of $11.4 million	139,388	$ 9	139,379
Exercise of stock options (in shares)		50,321
Exercise of stock options	345	$ 1	344
Exercise of warrants (in shares)		33,846
Exercise of warrants	447		447
APIC, Share-based Payment Arrangement, Increase for Cost Recognition	2,050		2,050
Foreign currency translation adjustment	(119)			(119)
Net loss	(52,807)				(52,807)
Ending balance (in shares) at Dec. 31, 2019		16,128,862
Ending balance at Dec. 31, 2019	129,220	$ 16	261,367	(119)	(132,044)
Increase (Decrease) in Temporary Equity [Roll Forward]
Repurchase of Series Seed convertible preferred stock, net of issuance costs of $11 thousand	0
Conversion of redeemable common stock into common stock	$ 0
Ending balance, convertible preferred stock (in shares) at Dec. 31, 2020
Ending balance, convertible preferred stock at Dec. 31, 2020
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Exercise of stock options (in shares)	17,689	17,689
Exercise of stock options	$ 127	$ 0	127
APIC, Share-based Payment Arrangement, Increase for Cost Recognition	$ 5,428		5,428
Issuance of shares under employee stock purchase plan (in shares)	26,643
Issuance of shares under employee stock purchase plan	$ 169		169
Vesting of restricted stock units, less shares withheld and retired to satisfy tax obligations (in shares)	132,537
Vesting of restricted stock units, less shares withheld and retired to satisfy tax obligations	$ (14)		(14)
Net loss	(62,131)				(62,131)
Ending balance (in shares) at Dec. 31, 2020		16,305,731
Ending balance at Dec. 31, 2020	$ 72,799	$ 16	$ 267,077	$ (119)	$ (194,175)