Stock-Based Compensation - Stock Option Activity and Related Information (Detail)
9 Months Ended
Sep. 30, 2016
$ / shares
shares
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]  
Shares, Outstanding at Beginning of Period | shares 3,000
Shares, Granted | shares 0
Shares, Exercised | shares 3,000
Shares, Forfeited | shares 0
Shares, Options Exercisable | shares 0
Weighted average exercise price per share, Outstanding at Beginning of Period | $ / shares $ 10.97
Weighted average exercise price per share, Granted | $ / shares 0
Weighted average exercise price per share, Exercised | $ / shares 10.97
Weighted average exercise price per share, Forfeited | $ / shares 0
Weighted average exercise price per share, Options Exercisable | $ / shares $ 0