Earnings (Loss) per Common Share - Antidilutive Securities Excluded From Computation of Diluted Net Loss per Common Share (Detail) - shares	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share	18,847,685,000	14,460,256,000	19,030,211,000	14,460,256,000
Unvested RSUs
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share	7,483,684,000	4,997,674,000	7,483,684,000	4,997,674,000
Vested and Unvested Options
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share	11,364,001,000	9,438,653,000	11,490,929,000	9,438,653,000
ESPP Share Purchase Rights
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share	0	23,929,000	55,598,000	23,929,000