Consolidated Statements of Convertible Preferred Stock and Stockholders' Deficit - USD ($) $ in Thousands	Total	Preferred Stock [Member] Convertible Preferred Stock [Member]	Common Stock [Member]	Additional Paid-in Capital [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Accumulated Deficit [Member]
Beginning balance at Dec. 31, 2018	$ (110,927)	$ 532,120	$ 3	$ 3,247		$ (114,177)
Beginning balance, shares at Dec. 31, 2018		210,863,764	2,998,017
Issuance of Series C convertible preferred stock, net of issuance costs of $50		$ 5,661
Issuance of Series C convertible preferred stock, net of issuance costs of $50, shares		1,779,093
Issuance of common stock upon exercise of stock options	613			613
Issuance of common stock upon exercise of stock options, shares			178,969
Vesting of restricted common stock	400		$ 1	399
Vesting of restricted common stock ,shares			860,490
Stock-based compensation expense	4,456			4,456
Unrealized gain (loss) on investments	325				$ 325
Net loss	(75,305)					(75,305)
Ending balance at Dec. 31, 2019	(180,438)	$ 537,781	$ 4	8,715	325	(189,482)
Ending balance, shares at Dec. 31, 2019		212,642,857	4,037,476
Extinguishment upon modification of Series C preferred stock	(177,789)	$ 177,789		(15,455)		(162,334)
Conversion of convertible preferred stock into common stock upon initial public offering	715,570	$ (715,570)	$ 62	715,508
Conversion of convertible preferred stock into common stock upon initial public offering, shares		(212,642,857)	61,992,534
Issuance of common stock in follow-on offering, net of discounts and issuance costs	425,293		$ 23	425,270
Issuance of common stock in follow-on offering, net of discounts and issuance costs, shares			23,000,000
Issuance of common stock upon exercise of stock options	1,216			1,216
Issuance of common stock upon exercise of stock options, shares			297,000
Vesting of restricted common stock	154		$ 1	153
Vesting of restricted common stock ,shares			579,825
Stock-based compensation expense	31,960			31,960
Unrealized gain (loss) on investments	(261)				(261)
Net loss	(52,412)					(52,412)
Ending balance at Dec. 31, 2020	763,293		$ 90	1,167,367	64	(404,228)
Ending balance, shares at Dec. 31, 2020			89,906,835
Purchase of common stock under ESPP	1,141		$ 1	1,140
Purchase of common stock under ESPP, shares			43,685
Issuance of common stock in follow-on offering, net of discounts and issuance costs	382,210		$ 15	382,195
Issuance of common stock in follow-on offering, net of discounts and issuance costs, shares			15,188,679
Issuance of common stock upon exercise of stock options	4,739		$ 1	4,738
Issuance of common stock upon exercise of stock options, shares			996,536
Vesting of restricted common stock	3			3
Vesting of restricted common stock ,shares			160,364
Stock-based compensation expense	48,454			48,454
Shares issued in connection with acquisition of ZebiAI	62,992		$ 2	62,990
Shares issued in connection with acquisition, shares			1,914,219
Unrealized gain (loss) on investments	(1,152)				(1,152)
Net loss	(363,872)					(363,872)
Ending balance at Dec. 31, 2021	$ 897,808		$ 109	$ 1,666,887	$ (1,088)	$ (768,100)
Ending balance, shares at Dec. 31, 2021			108,210,318