Convertible Preferred Stock and Stockholders' Equity (Details 6) - USD ($) $ in Thousands	3 Months Ended				6 Months Ended
	Jun. 30, 2022	Mar. 31, 2022	Jun. 30, 2021	Mar. 31, 2021	Jun. 30, 2022	Jun. 30, 2021
Class Of Stock [Line Items]
Balance	$ 633,393	$ 678,838	$ 790,095	$ 384,445	$ 678,838	$ 384,445
Exercise of stock options, net of issuance costs	3,184	3,001	3,681	5,648
Issuance of common stock upon vesting of restricted stock units		1
Stock-based compensation	20,542	19,331	13,254	12,976
Public offering of common stock and issuance of pre-funded warrants, net of issuance costs				432,445
Unrealized gain (loss) on investments	(531)	(2,088)	174	(330)
Net loss	(76,105)	(65,690)	(55,133)	(45,089)	(141,795)	(100,222)
Balance	$ 580,483	$ 633,393	$ 752,071	$ 790,095	$ 580,483	$ 752,071
Class A Convertible Preferred Shares
Class Of Stock [Line Items]
Balance (in shares)	2,794,549	2,794,549	2,794,549	2,794,549	2,794,549	2,794,549
Balance (in shares)	2,794,549	2,794,549	2,794,549	2,794,549	2,794,549	2,794,549
Preferred Stock | Class A Convertible Preferred Shares
Class Of Stock [Line Items]
Balance	$ 3	$ 3	$ 3	$ 3	$ 3	$ 3
Balance	3	3	3	3	3	3
Common Stock
Class Of Stock [Line Items]
Balance	$ 97	$ 96	$ 94	$ 88	$ 96	$ 88
Balance (in shares)	96,538,084	95,726,962	93,888,679	87,722,237	95,726,962	87,722,237
Exercise of stock options, net of issuance costs				$ 1
Exercise of stock options, net of issuance costs (in shares)	251,486	398,415	368,947	613,015
Issuance of common stock upon vesting of restricted stock units		$ 1
Issuance of common stock upon vesting of restricted stock units (in shares)	73,227	412,707	7,500	430,620
Public offering of common stock and issuance of pre-funded warrants, net of issuance costs				$ 5
Public offering of common stock and issuance of pre-funded warrants, net of issuance costs(in shares)				5,122,807
Balance	$ 97	$ 97	$ 94	$ 94	$ 97	$ 94
Balance (in shares)	96,862,797	96,538,084	94,265,126	93,888,679	96,862,797	94,265,126
Additional Paid In Capital
Class Of Stock [Line Items]
Balance	$ 1,470,916	$ 1,448,584	$ 1,392,279	$ 941,216	$ 1,448,584	$ 941,216
Exercise of stock options, net of issuance costs	3,184	3,001	3,681	5,647
Stock-based compensation	20,542	19,331	13,254	12,976
Public offering of common stock and issuance of pre-funded warrants, net of issuance costs				432,440
Balance	1,494,642	1,470,916	1,409,214	1,392,279	1,494,642	1,409,214
Accumulated Other Comprehensive Gain (Loss)
Class Of Stock [Line Items]
Balance	(2,850)	(762)	(260)	70	(762)	70
Unrealized gain (loss) on investments	(531)	(2,088)	174	(330)
Balance	(3,381)	(2,850)	(86)	(260)	(3,381)	(86)
Accumulated Deficit
Class Of Stock [Line Items]
Balance	(834,773)	(769,083)	(602,021)	(556,932)	(769,083)	(556,932)
Net loss	(76,105)	(65,690)	(55,133)	(45,089)
Balance	$ (910,878)	$ (834,773)	$ (657,154)	$ (602,021)	$ (910,878)	$ (657,154)