Quarterly report pursuant to Section 13 or 15(d)

Stock-Based Compensation - Summary of Activity of Restricted Stock Units (Detail)

v3.19.2
Stock-Based Compensation - Summary of Activity of Restricted Stock Units (Detail) - Restricted Stock Units [Member]
6 Months Ended
Jun. 30, 2019
$ / shares
shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]  
Number of restricted stock units outstanding, Unvested beginning balance | shares 1,051,414
Number of restricted stock units outstanding, Granted | shares 100,000
Number of restricted stock units outstanding, Vested | shares (168,718)
Number of restricted stock units outstanding, Forfeited | shares (2,000)
Number of restricted stock units outstanding, Unvested ending balance | shares 980,696
Weighted-average grant date fair value, Unvested beginning balance | $ / shares $ 10.15
Weighted-average grant date fair value, Granted | $ / shares 12.48
Weighted-average grant date fair value, Vested | $ / shares 8.36
Weighted-average grant date fair value, Forfeited | $ / shares 8.00
Weighted-average grant date fair value, Unvested ending balance | $ / shares $ 10.62