Quarterly report pursuant to Section 13 or 15(d)

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

v3.8.0.1
Stock Based Compensation - Schedule of Restricted Stock Units Activity (Detail) - Restricted Stock Units (RSUs) [Member]
3 Months Ended
Mar. 31, 2018
$ / shares
shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]  
Number of Options, Outstanding | shares 2,274,325
RSUs granted | shares 740,766
RSUs forfeited | shares (31,750)
RSUs vested | shares (341,936)
Number of Options, Outstanding | shares 2,641,405
Weighted Average Grant Date Fair Value, Beginning Balance | $ / shares $ 13.75
Weighted Average Grant Date Fair Value, RSUs granted | $ / shares 20.32
Weighted Average Grant Date Fair Value, RSUs forfeited | $ / shares 12.76
Weighted Average Grant Date Fair Value, RSUs vested | $ / shares 14.59
Weighted Average Grant Date Fair Value, Ending Balance | $ / shares $ 15.50