• Filing Date: 2018-03-07
  • Form Type: 10-K
  • Description: Annual report
v3.8.0.1
Stock-Based Compensation - Summary of Company's Stock Option Plan Activity (Detail) - USD ($)
$ / shares in Units, $ in Thousands
12 Months Ended
Dec. 31, 2017
Dec. 31, 2016
Dec. 31, 2015
Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]        
Granted, Number of options 110,000      
Exercised, Number of Options (30,000) (60,000) (120,000)  
Outstanding, Number of Options 130,000 50,000 110,000 230,000
Exercisable, Number of Options 20,000      
Granted, Weighted Average Exercise Price $ 40.00      
Exercised, Weighted-Average Exercise Price 2.50 $ 2.50 $ 2.82  
Outstanding, Weighted Average Exercise Price 34.82 $ 4.02 $ 3.19 $ 3.00
Exercisable, Weighted-Average Exercise Price $ 6.30      
Outstanding, Weighted-Average Remaining Contractual Term 8 years 2 months 12 days 2 years 3 months 19 days 2 years 3 months 19 days 3 years
Exercisable, Weighted-Average Remaining Contractual Term 3 years 8 months 12 days      
Outstanding, Aggregate Intrinsic Value $ 472 $ 1,773 $ 3,482 $ 9,256
Exercisable, Aggregate Intrinsic Value $ 472