Net Earnings per Common Share - Additional Information (Detail) - shares |
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
Jun. 30, 2015 |
Jun. 30, 2014 |
Jun. 30, 2015 |
Jun. 30, 2014 |
|
| Earnings Per Share [Abstract] | ||||
| Anti-dilutive potential common shares are excluded from the diluted earnings per share computation | 0 | 0 | 102,397 | 0 |