Net Loss Per Share - Anti-Dilutive Securities of Common Stock Excluded from Calculation of Diluted Net Loss Per Share (Details) - shares shares in Thousands	9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Anti-dilutive securities not included in diluted net loss per share (in shares)	46,618	49,746
Series A Convertible Preferred Stock
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Anti-dilutive securities not included in diluted net loss per share (in shares)		29
Options to purchase common stock and employee stock purchase plan
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Anti-dilutive securities not included in diluted net loss per share (in shares)	3,142	3,524
Unvested restricted stock unit awards
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Anti-dilutive securities not included in diluted net loss per share (in shares)	8,744	8,733
Warrants to purchase common stock
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Anti-dilutive securities not included in diluted net loss per share (in shares)	17,486	20,214
Senior Convertible Notes
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Anti-dilutive securities not included in diluted net loss per share (in shares)	17,246	17,246