Annual report pursuant to Section 13 and 15(d)

Supplementary Balance Sheet Information - Additional Information (Detail)

v3.7.0.1
Supplementary Balance Sheet Information - Additional Information (Detail) - USD ($)
 12 Months Ended
Dec. 31, 2016
Dec. 31, 2015
Accounts Receivable [Abstract]    
Allowances for doubtful accounts $ 1,200,000 $ 1,800,000
Provision for sales returns 210,000 210,000
Provision for excess and obsolete inventory 1,700,000 2,100,000
Deferred revenue recognized 18,000 119,000
Litigation Settlement Receivable 1,400,000  
Legal settlement at present value 1,200,000  
Litigation Expense Recovered   731,000
Settlement Expense For Dismissal of Patent Infringement Lawsuit Recovered 68,000  
Deferred royalty revenue recognized 119,000 119,000
Deferred Royalties 142,000 261,000
Settled Litigation    
Accounts Receivable [Abstract]    
Deferred royalty revenue, net $ 379,000  
Licensing Agreements United States    
Accounts Receivable [Abstract]    
License period 3 years  
Licensing Agreements Outside of United States    
Accounts Receivable [Abstract]    
License period 5 years  
Assets Held Under Capital Lease    
Accounts Receivable [Abstract]    
Capital leased assets, Gross $ 378,000 590,000
Accumulated depreciation related to assets held under capital lease $ 227,000 $ 118,000