Stock-Based Compensation - Restricted Stock Awards Activity and Related Information (Detail) - Restricted Stock [Member] |
9 Months Ended |
|---|---|
|
Sep. 30, 2016
shares
| |
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | |
| Shares, Outstanding at Beginning of Period | 783,310 |
| Shares, Granted | 628,013 |
| Shares, Vested | 351,220 |
| Shares, Forfeited/Cancelled | 32,520 |
| Shares, Outstanding End of Period | 1,027,583 |