Annual report pursuant to Section 13 and 15(d)

Share-based Compensation - Summary of Information under Plans (Detail)

v3.3.1.900
Share-based Compensation - Summary of Information under Plans (Detail) - USD ($)
$ / shares in Units, $ in Thousands
12 Months Ended
Dec. 31, 2015
Dec. 31, 2014
Dec. 31, 2013
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]      
Grant date fair value of options granted $ 78 $ 583 $ 1,053
Fair value of options vested 2,668 2,141 920
Total intrinsic value of options exercised 488 353 485
Cash received from options exercised $ 616 $ 467 $ 525
Weighted-average estimated fair value per share of options granted (in usd per share) $ 3.62 $ 4.79 $ 4.48