Summary of Significant Accounting Policies - Summary of Common Stock Equivalents Outstanding (Detail) - shares |
6 Months Ended | |
---|---|---|
Jun. 30, 2019 |
Jun. 30, 2018 |
|
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] | ||
Total potentially dilutive shares | 7,039,525 | 6,270,457 |
Options to Purchase Common Stock [Member] | ||
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] | ||
Total potentially dilutive shares | 6,717,144 | 6,261,528 |
Unvested Restricted Common Stock [Member] | ||
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] | ||
Total potentially dilutive shares | 322,381 | 8,929 |