Annual report pursuant to Section 13 and 15(d)

Summary of Significant Accounting Policies - Additional Information (Detail)

v3.8.0.1
Summary of Significant Accounting Policies - Additional Information (Detail)
 12 Months Ended
Dec. 31, 2017
USD ($)
Segment
shares
Dec. 31, 2016
USD ($)
shares
Dec. 31, 2015
USD ($)
shares
Accounting Policies [Line Items]      
Restricted cash $ 251,000 $ 251,000  
Depreciation expense $ 1,203,000 997,000 $ 817,000
Number of reporting unit | Segment 1    
Undelivered elements (training, installation, product and support services) $ 980,000 1,404,000  
Provision for sales returns 210,000 210,000  
Extended warranty contracts $ 1,600,000 1,500,000  
Revenue recognition, percentage of fair value of trade-in exchange 25.00%    
Advertising costs $ 298,000 351,000 929,000
Compensation cost related to stock options 2,207,000 3,065,000 $ 3,350,000
Total unrecognized compensation cost $ 3,400,000 $ 4,000,000  
Unrecognized share based compensation cost to be recognized over weighted-average period 2 years    
Excise tax on medical devices, effective start date Jan. 01, 2018    
Excise tax on medical devices, suspension end date Jan. 01, 2020    
Outstanding stock options, restricted stock units and warrants excluded from diluted loss per share | shares 16,918,000 20,537,000 17,371,000
Executives      
Accounting Policies [Line Items]      
Fair value assumptions, forfeiture rate 6.38%    
Employees      
Accounting Policies [Line Items]      
Fair value assumptions, forfeiture rate 40.90%    
U S | Maximum      
Accounting Policies [Line Items]      
Product warrant period 2 years 2 years  
U S | Waterlase Systems      
Accounting Policies [Line Items]      
Product warrant period 1 year    
International | Maximum      
Accounting Policies [Line Items]      
Product warrant period 28 months 28 months  
International | Waterlase Systems      
Accounting Policies [Line Items]      
Product warrant period 16 months