v3.3.1.900
Stockholders' Equity - Additional Information (Detail)
 3 Months Ended 12 Months Ended
Jun. 30, 2010
USD ($)
$ / shares
Dec. 31, 2015
USD ($)
Plans
$ / shares
shares
Dec. 31, 2014
USD ($)
$ / shares
shares
Dec. 31, 2013
USD ($)
$ / shares
shares
Jun. 30, 2015
shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Preferred stock, shares authorized   10,000,000 10,000,000    
Preferred stock, shares outstanding   0 0    
Common stock, shares authorized   40,000,000 40,000,000    
Common stock, shares outstanding   14,389,000 14,358,000    
Number of equity incentive plans | Plans   2      
Shares outstanding under equity incentive plans   1,257,000 980,000    
Term of vesting schedule   10 years      
Vested share exercised   3 months      
Fair value assumption, risk-free interest rates   1.94% 1.56% 1.81%  
Fair value assumption, expected dividend yields   0.00% 0.00% 0.00%  
Aggregate intrinsic value closing stock price | $ / shares   $ 1.58      
Equity ownership percentage to benefit China employees 38.00%        
Price of warrant | $ / shares $ 1.00        
Vesting period of warrant   Vesting to occur one-third upon the first anniversary of the warrant and the remaining two-thirds to vest on a monthly basis over the succeeding 24 months.      
Investment warrants expiration period (years) 6 years        
Warrant exercise date   May 05, 2013      
Fair value of options granted | $ / shares   $ 1.25 $ 0.93 $ 0.58  
Unrecognized compensation expense related to non-vested stock options | $   $ 407,000      
Recognition of unrecognized compensation expense, weighted-average period (in years)   1 year 8 months 12 days      
Fair value of options that vested | $   $ 205,000 $ 80,000 $ 68,000  
Stock issued during period, stock options exercised   30,000 174,000 0  
Cash received from exercise of stock options | $   $ 27,000 $ 137,000    
Stock options exercise price | $ / shares   $ 0.89 $ 0.79    
Minimum [Member]          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Period of option granted vest   2 years      
Fair value assumption, expected volatility   93.00% 93.00% 93.00%  
Fair value assumption, expected term (years)   4 years 4 years 4 years  
Maximum [Member]          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Period of option granted vest   3 years      
Fair value assumption, expected volatility   102.00% 102.00% 102.00%  
Fair value assumption, expected term (years)   6 years 6 years 6 years  
2006 Equity Incentive Plan [Member]          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Shares outstanding under equity incentive plans   942,000      
Common stock available for future issuance   0      
Share-based compensation arrangement by share-based payment award, award vesting rights, percentage   100.00%      
2015 Equity Incentive Plan [Member]          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Shares outstanding under equity incentive plans   315,000      
Common stock available for future issuance   899,000      
Common stock authorized for issuance there-under         1,205,749
2015 Equity Incentive Plan [Member] | Maximum [Member]          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Common stock available for future issuance   958,668      
Hong Kong Subsidiary [Member]          
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Value funded to affiliates | $ $ 1,000,000        
Agreed additional funding to affiliates | $ $ 1,000,000        
Estimated fair value of warrants | $   $ 365,000      
Warrant performance period (years)   3 years      
Stock expenses on equity-based payments related to warrant | $   $ 0 $ 0 $ 40,000