XML 59 R49.htm IDEA: XBRL DOCUMENT v3.10.0.1
Summary of Stock Option (Detail)
 6 Months Ended
Jun. 30, 2018
USD ($)
$ / shares
shares
Options  
Beginning balance | shares 1,456,200
Grants | shares 205,750
Cancellations | shares (9,250)
Expirations | shares (13,875)
Ending balance | shares 1,638,825
Options exercisable at End of Period | shares 1,312,395
Weighted-average exercise price  
Beginning balance | $ / shares $ 13.64
Grants | $ / shares 13.56
Cancellations | $ / shares 17.95
Expirations | $ / shares 17.43
Ending balance | $ / shares 13.57
Options exercisable at End of Period | $ / shares $ 13.32
Weighted-average remaining contractual life (years)  
Options outstanding, Ending balance 4 years 8 months 12 days
Options exercisable, Ending balance 3 years 8 months 12 days
Aggregate intrinsic value  
Options outstanding, end of period | $ $ 1,512,990
Options exercisable, end of period | $ $ 1,512,990