Stockholders' Equity - Additional Information (Detail) - shares |
12 Months Ended | |||
|---|---|---|---|---|
Dec. 31, 2016 |
Dec. 31, 2015 |
Dec. 31, 2014 |
Dec. 31, 2013 |
|
| Stockholders Equity Note [Abstract] | ||||
| Existing long-term incentive plan | 200,000 | |||
| Shares available for future award under proposed long term incentive plan | 163,500 | |||
| Shares awarded under proposed long term incentive plan | 13,500 | 8,000 | 8,000 | |
| Number of shares authorized for repurchase | 2,000,000 | |||
| Shares available for repurchase under the plan | 1,951,000 | |||