Quarterly report pursuant to Section 13 or 15(d)

Stock Based Compensation Plans (Additional Information) (Detail)

v3.8.0.1
Stock Based Compensation Plans (Additional Information) (Detail) - USD ($)
3 Months Ended 12 Months Ended
Mar. 31, 2018
Mar. 31, 2017
Dec. 31, 2017
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]      
Exercisable Options Outstanding Shares 850,721    
Weighted average exercise price per share $ 4.55    
Unvested Options Outstanding, Shares 630,088    
Unvested Options Outstanding, Weighted average exercise price $ 5.57    
Unvested Warrant Outstanding Weighted average remaining life (yrs) 8 years 8 months 12 days    
Weighted average remaining contractual term on unvested options 6 years 7 months 6 days    
Unrecognized stock compensation expense $ 3,130,000    
Weighted average recognition period 2 years 9 months 18 days    
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term 7 years 6 months   7 years 7 months 6 days
Share-Based Compensation $ 424,700 $ 210,074  
Executive Officer [Member]      
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]      
Unrecognized stock compensation expense $ 458,000    
Weighted average recognition period 3 years 1 month 6 days    
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested Issued , Number     100,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, NonVested in Period, Fair Value     $ 590,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value     $ 5.90
External Board [Member]      
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]      
Unrecognized stock compensation expense $ 83,750    
Stock Issued During Period, Shares, Issued for Services     50,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Weighted Average Grant Date Fair Value     $ 6.70
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Fair Value     $ 335,000