Equity - Summary of Future Issuance of Common Stock Shares (Detail) - shares shares in Thousands	Dec. 31, 2021	Dec. 31, 2020
Schedule of Capitalization [Line Items]
Common shares reserved for future issuance (in shares)	14,831	10,369
2013 Stock Option and Incentive Plan
Schedule of Capitalization [Line Items]
Common shares reserved for future issuance (in shares)	2,250	2,545
2013 Employee Stock Purchase Plan
Schedule of Capitalization [Line Items]
Common shares reserved for future issuance (in shares)	1,347	67
Options to purchase common stock
Schedule of Capitalization [Line Items]
Common shares reserved for future issuance (in shares)	5,534	6,262
Restricted stock units
Schedule of Capitalization [Line Items]
Common shares reserved for future issuance (in shares)	3,427	1,495
Pre-funded warrants
Schedule of Capitalization [Line Items]
Common shares reserved for future issuance (in shares)	2,273	0