Quarterly report pursuant to Section 13 or 15(d)

Schedule of Stock Options Activity (Detail)

v3.8.0.1
Schedule of Stock Options Activity (Detail) - USD ($)
 3 Months Ended 12 Months Ended
Mar. 31, 2018
Dec. 31, 2017
Shares    
Options exercised (75,000)  
Employee Stock Option [Member]    
Shares    
Beginning balance 1,141,040  
Options granted 30,000  
Options exercised (129,536)  
Options forfeited 0  
Ending balance 1,041,504 1,141,040
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Number 1,041,504  
Weighted Average Exercise Price    
Beginning balance $ 3.95  
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price 9.25  
Share-based Compensation Arrangements by Share-based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price 6.11  
Share-based Compensation Arrangements by Share-based Payment Award, Options, Forfeitures in Period, Weighted Average Exercise Price 0  
Ending balance 4.09 $ 3.95
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Weighted Average Exercise Price $ 4.09  
Weighted Average Remaining Contractual Term (Years)    
Beginning Balance 5 years 7 months 28 days 5 years 9 months 14 days
Options exercisable 5 years 7 months 28 days  
Aggregate Intrinsic Value    
Beginning Balance $ 19.81  
Options exercised 15.03  
Ending balance 11.86 $ 19.81
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value $ 11.86  
Allied Pacific of California [Member]    
Shares    
Beginning balance 853,800  
Options granted 0  
Options exercised 0  
Options forfeited 0  
Ending balance 853,800 853,800
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Number 853,800  
Weighted Average Exercise Price    
Beginning balance $ 0.167  
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price 0  
Share-based Compensation Arrangements by Share-based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price 0  
Share-based Compensation Arrangements by Share-based Payment Award, Options, Forfeitures in Period, Weighted Average Exercise Price 0  
Ending balance 0.167 $ 0.167
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Weighted Average Exercise Price $ 0.167  
Weighted Average Remaining Contractual Term (Years)    
Beginning Balance 1 year 6 months 1 year 9 months
Options exercisable 1 year 6 months  
Aggregate Intrinsic Value    
Beginning Balance $ 508,864  
Ending balance 508,864 $ 508,864
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value $ 508,864