Annual report pursuant to Section 13 and 15(d)

Stock-Based Compensation - Additional Information (Detail)

v3.21.1
Stock-Based Compensation - Additional Information (Detail)
12 Months Ended
Jan. 02, 2020
$ / shares
shares
Jul. 23, 2019
grantee
$ / shares
shares
Dec. 31, 2020
USD ($)
stockPlan
$ / shares
shares
Dec. 31, 2019
USD ($)
$ / shares
shares
Oct. 11, 2016
shares
Apr. 01, 2010
shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Number of equity incentive plans | stockPlan     2      
Options granted maximum exercisable period     10 years      
Issuance of shares under stock options plans (shares)     1,000      
Stock appreciation rights (shares)     0      
Restricted stock awarded under Stock Option Plans (shares)     12,000      
Granted (shares)     20,000 20,000    
Granted (usd per share) | $ / shares     $ 5.53 $ 5.89    
Options exercised (shares)     0 0    
Stock-based compensation expense | $     $ 179,000 $ 263,000    
Employee            
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Unrecognized compensation cost | $     $ 62,000      
Unrecognized compensation cost, period for recognition     1 year 29 days      
2011 Equity Incentive Plan            
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Number of common stock shares authorized for issuance (shares)         105,000  
Shares available for future awards (shares)     39,000      
2008 Stock Option Plan            
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Shares of common stock reserved for issuance (shares)           18,000
Employee Stock Option            
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Grant date fair value (usd per share) | $ / shares     $ 4.45 $ 4.32    
Dividend yield     0.00% 0.00%    
Restricted Stock            
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Compensation cost not yet recognized, equity instruments other than options | $     $ 0      
Nonemployee | Employee Stock Option            
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Granted (shares) 20,000 3,000        
Number of grantees | grantee   5        
Common stock, vesting period 12 months 12 months        
Granted (usd per share) | $ / shares $ 5.53 $ 4.50        
Grant date fair value (usd per share) | $ / shares $ 4.45          
Discontinuing Operations            
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Stock-based compensation expense | $     $ (6,000) $ 107,000