Annual report pursuant to Section 13 and 15(d)

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

v3.10.0.1
Stock Based Compensation - Schedule of Restricted Stock Units Activity (Detail) - Restricted Stock Units (RSUs) [Member]
12 Months Ended
Dec. 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 1,378,301
RSUs forfeited | shares (220,433)
RSUs vested | shares (963,019)
Number of Options, Outstanding | shares 2,469,174
Weighted Average Grant Date Fair Value, Beginning Balance | $ / shares $ 13.75
Weighted Average Grant Date Fair Value, RSUs granted | $ / shares 15.89
Weighted Average Grant Date Fair Value, RSUs forfeited | $ / shares 14.36
Weighted Average Grant Date Fair Value, RSUs vested | $ / shares 13.30
Weighted Average Grant Date Fair Value, Ending Balance | $ / shares $ 15.07