Quarterly report pursuant to Section 13 or 15(d)

Common Stock - Additional Information (Detail)

v3.8.0.1
Common Stock - Additional Information (Detail) - USD ($)
 3 Months Ended 7 Months Ended
Sep. 14, 2017
Mar. 31, 2018
Mar. 31, 2017
Mar. 31, 2018
Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Common stock, shares authorized   75,000,000   75,000,000 75,000,000
Common stock, par value   $ 0.001   $ 0.001 $ 0.001
Preferred stock, shares authorized   5,000,000   5,000,000  
Preferred stock, par value   $ 0.001   $ 0.001  
Initial purchase of units consisting of common stock and warrants issued   $ 1,105,000      
Common stock, shares issued   12,756,752   12,756,752 11,956,752
Stock option exercises, Shares   0 0    
Restricted stock unit settlements   0 0    
Common shares reserved for options currently outstanding   1,112,406   1,112,406 1,115,647
Common shares reserved for awards currently outstanding     0    
Number of stock options granted   0 0    
Number of warrants exercised   0 0    
Stock Options [Member] | Employees and Consultants [Member]          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Award vesting period   4 years      
Restricted Stock Unit [Member]          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Award vesting period   4 years      
Common shares reserved for awards currently outstanding   205,104   205,104 210,160
2017 Equity Incentive Plan [Member]          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Award expiration period   10 years      
2017 Equity Incentive Plan [Member] | Stock Options [Member]          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Common shares reserved for issuance under incentive plan   1,049,100   1,049,100  
2010 Performance Incentive Plan [Member]          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Award expiration period   10 years      
2010 Performance Incentive Plan [Member] | Stock Options [Member]          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Common shares reserved for issuance under incentive plan   264,876   264,876  
Common shares reserved for options currently outstanding   59,772   59,772  
2010 Performance Incentive Plan [Member] | Restricted Stock Unit [Member]          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Common shares reserved for awards currently outstanding   205,104   205,104  
Minimum [Member] | Stock Options [Member]          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Award expiration period   7 years      
Minimum [Member] | Stock Options [Member] | Board of Directors [Member]          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Award vesting period   1 year      
Minimum [Member] | 2017 Equity Incentive Plan [Member] | Employees and Consultants [Member]          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Award vesting period   3 years      
Minimum [Member] | 2017 Equity Incentive Plan [Member] | Board of Directors [Member]          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Award vesting period   1 year      
Minimum [Member] | 2010 Performance Incentive Plan [Member] | Employees and Consultants [Member]          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Award vesting period   3 years      
Minimum [Member] | 2010 Performance Incentive Plan [Member] | Board of Directors [Member]          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Award vesting period   1 year      
Maximum [Member] | Stock Options [Member]          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Award expiration period   10 years      
Maximum [Member] | Stock Options [Member] | Board of Directors [Member]          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Award vesting period   3 years      
Maximum [Member] | 2017 Equity Incentive Plan [Member] | Employees and Consultants [Member]          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Award vesting period   4 years      
Maximum [Member] | 2017 Equity Incentive Plan [Member] | Board of Directors [Member]          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Award vesting period   3 years      
Maximum [Member] | 2010 Performance Incentive Plan [Member] | Employees and Consultants [Member]          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Award vesting period   4 years      
Maximum [Member] | 2010 Performance Incentive Plan [Member] | Board of Directors [Member]          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Award vesting period   3 years      
LPC [Member]          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Common stock, par value $ 0.001        
Common stock value right to sell, maximum $ 11,000,000        
Initial purchase of common stock       328,947  
Common stock, purchase price $ 1.00        
Additional common stock value right to sell, maximum $ 10,000,000        
Additional purchase of common stock, maximum 80,000        
Common stock, shares issued 123,516        
Gross proceeds $ 0        
Common stock, shares issued       1,673,778  
Gross proceeds       $ 3,400,000  
Offering expenses       500,000  
Common stock available for sale under offering   $ 7,600,000   $ 7,600,000  
LPC [Member] | Minimum [Member]          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Common stock, purchase price $ 2.00        
LPC [Member] | Units [Member]          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Initial purchase of common stock 328,947        
Common stock, purchase price $ 3.04        
Purchase agreement, description   Unit consisting of (a) one share of our Common Stock and (b) one warrant to purchase one-quarter of a share of Common Stock at an exercise price of $3.496 per share, or Warrant. Each Warrant is exercisable six months following the issuance date until the date that is five years and six months after the issuance date and is subject to customary adjustments.      
Exercise price per unit of warrant $ 3.496        
Initial purchase of units consisting of common stock and warrants issued $ 1,000,000        
LPC [Member] | Other Units [Member]          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Number of warrants issued 0