Condensed Consolidated Statements of Changes in Stockholders' Equity - USD ($) $ in Thousands	Total	Convertible Preferred Stock	Class A and Class B Common Stock	Additional Paid in Capital	Accumulated Deficit	Accumulated Other Comprehensive Income (Loss)
Beginning balance (in shares) at Dec. 31, 2019		22,173,216	12,193,677
Beginning balance at Dec. 31, 2019	$ 87,679	$ 107,953	$ 0	$ 2,288	$ (22,586)	$ 24
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of Class A common stock from exercise of options (in shares)			40,207
Issuance of Class A common stock from exercise of options	24			24
Vesting of early exercised stock options and restricted common stock	4			4
Stock-based compensation	579			579
Other comprehensive loss	533					533
Net loss	(5,493)				(5,493)
Ending balance (in shares) at Mar. 31, 2020		22,173,216	12,233,884
Ending balance at Mar. 31, 2020	83,326	$ 107,953	$ 0	2,895	(28,079)	557
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of Class A common stock from exercise of options (in shares)			11,877
Issuance of Class A common stock from exercise of options	28			28
Repurchase of Class A common stock (in shares)			(215,245)
Repurchase of Class A common stock	0
Vesting of early exercised stock options and restricted common stock	10			10
Issuance of stock (in shares)		6,853,571
Issuance of stock	54,896	$ 54,896
Stock-based compensation	808			808
Other comprehensive loss	(255)					(255)
Net loss	(6,117)				(6,117)
Ending balance (in shares) at Jun. 30, 2020		29,026,787	12,030,516
Ending balance at Jun. 30, 2020	132,696	$ 162,849	$ 0	3,741	(34,196)	302
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of Class A common stock from exercise of options (in shares)			611,824
Issuance of Class A common stock from exercise of options	42			42
Vesting of early exercised stock options and restricted common stock	49			49
Distribution of PrognomIQ shares	(40)			(40)
Stock-based compensation	1,177			1,177
Other comprehensive loss	(159)					(159)
Net loss	(8,229)				(8,229)
Ending balance (in shares) at Sep. 30, 2020		29,026,787	12,642,340
Ending balance at Sep. 30, 2020	$ 125,536	$ 162,849	$ 0	4,969	(42,425)	143
Beginning balance (in shares) at Dec. 31, 2020	59,261,051	0	59,261,051
Beginning balance at Dec. 31, 2020	$ 431,609	$ 0	$ 1	486,915	(55,361)	54
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of Class A common stock from exercise of options (in shares)			399,174
Issuance of Class A common stock from exercise of options	171			171
Repurchase of Class A common stock (in shares)			(876)
Vesting of early exercised stock options and restricted common stock	44			44
Issuance of stock (in shares)			1,650,000
Issuance of stock	102,959			102,959
Return of profit	11,403			11,403
Stock-based compensation	6,039			6,039
Other comprehensive loss	(26)					(26)
Net loss	(16,429)				(16,429)
Ending balance (in shares) at Mar. 31, 2021		0	61,309,349
Ending balance at Mar. 31, 2021	$ 535,770	$ 0	$ 1	607,531	(71,790)	28
Beginning balance (in shares) at Dec. 31, 2020	59,261,051	0	59,261,051
Beginning balance at Dec. 31, 2020	$ 431,609	$ 0	$ 1	486,915	(55,361)	54
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of Class A common stock from exercise of options (in shares)	760,383
Ending balance (in shares) at Sep. 30, 2021	61,653,898	0	61,653,898
Ending balance at Sep. 30, 2021	$ 515,196	$ 0	$ 1	621,994	(106,791)	(8)
Beginning balance (in shares) at Mar. 31, 2021		0	61,309,349
Beginning balance at Mar. 31, 2021	535,770	$ 0	$ 1	607,531	(71,790)	28
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of Class A common stock from exercise of options (in shares)			132,766
Issuance of Class A common stock from exercise of options	236			236
Repurchase of Class A common stock (in shares)			(18,852)
Vesting of early exercised stock options and restricted common stock	285			285
Stock-based compensation	6,431			6,431
Other comprehensive loss	(62)					(62)
Net loss	(16,616)				(16,616)
Ending balance (in shares) at Jun. 30, 2021		0	61,423,263
Ending balance at Jun. 30, 2021	526,044	$ 0	$ 1	614,483	(88,406)	(34)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of Class A common stock from exercise of options (in shares)			230,635
Issuance of Class A common stock from exercise of options	631			631
Vesting of early exercised stock options and restricted common stock	94			94
Stock-based compensation	6,786			6,786
Other comprehensive loss	26					26
Net loss	$ (18,385)				(18,385)
Ending balance (in shares) at Sep. 30, 2021	61,653,898	0	61,653,898
Ending balance at Sep. 30, 2021	$ 515,196	$ 0	$ 1	$ 621,994	$ (106,791)	$ (8)