Annual report pursuant to Section 13 and 15(d)

Summary of Significant Accounting Policies and Nature of Operations - Additional Information (Details)

v3.19.1
Summary of Significant Accounting Policies and Nature of Operations - Additional Information (Details)
 3 Months Ended 6 Months Ended 9 Months Ended 12 Months Ended
Sep. 29, 2018
USD ($)
Jun. 30, 2018
USD ($)
Mar. 31, 2018
USD ($)
Dec. 30, 2017
USD ($)
Sep. 30, 2017
USD ($)
Jul. 01, 2017
USD ($)
Apr. 01, 2017
USD ($)
Sep. 29, 2018
USD ($)
Sep. 29, 2018
USD ($)
Dec. 29, 2018
USD ($)
item
Dec. 30, 2017
USD ($)
Dec. 31, 2016
USD ($)
segment
Property, Plant and Equipment [Line Items]                        
Net (loss) income $ (180,000) $ (797,000) $ 568,000 $ (4,079,000) $ 919,000 $ 26,918,000 $ 257,000 $ (229,000) $ (409,000) $ (4,889,000) $ 24,015,000  
Number of suppliers | item                   1    
Inventory in-transit       10,164,000           $ 9,701,000 10,164,000  
Capitalized website and software development costs                   49,000 $ 56,000  
Impairment loss on intangible assets                   0    
Impairment loss on property and equipment                   $ 0    
Catalog amortization period                   9 months    
Advertising revenue as a percentage of total revenue                   1.00% 1.00% 1.00%
Credits for returned products                   $ 19,691,000 $ 21,837,000  
Warranty, coverage period                   30 days    
Warranty, unlimited product replacement, coverage period                   5 years    
Warranty, one-time product replacement, coverage period, option one                   5 years    
Warranty, one-time product replacement, coverage period, option two                   3 years    
Advertising costs                   $ 20,942,000 21,055,000  
Unrecognized tax benefits, interest or penalties                   0    
Number of operating segments | segment                       2
Effect of new accounting adoption       255,000             255,000  
Decrease to accumulated deficit due to adoption of new accounting pronouncement       (132,996,000)           $ (137,791,000) (132,996,000)  
Minimum                        
Property, Plant and Equipment [Line Items]                        
Length Of Fiscal Year                   364 days    
Standard product warranty, recognition period                   1 year    
Maximum                        
Property, Plant and Equipment [Line Items]                        
Length Of Fiscal Year                   371 days    
Standard product warranty, recognition period                   5 years    
Website and Software Development                        
Property, Plant and Equipment [Line Items]                        
Capitalized website and software development costs                   $ 3,883,000 3,914,000  
Capitalized website and software development cost amount       17,974,000           19,234,000 17,974,000 $ 17,974,000
Capitalized website and software development costs accumulated amortization and impairment amount       14,429,000           $ 16,425,000 14,429,000  
Website and Software Development | Minimum                        
Property, Plant and Equipment [Line Items]                        
Amortization on a straight-line basis, period                   2 years    
Website and Software Development | Maximum                        
Property, Plant and Equipment [Line Items]                        
Amortization on a straight-line basis, period                   3 years    
Cost of Sales                        
Property, Plant and Equipment [Line Items]                        
Freight and shipping expenses                   $ 43,674,000 40,565,000  
Employee Stock Option | Minimum                        
Property, Plant and Equipment [Line Items]                        
Stock options vesting period                   3 years    
Employee Stock Option | Maximum                        
Property, Plant and Equipment [Line Items]                        
Stock options vesting period                   4 years    
Accumulated Deficit                        
Property, Plant and Equipment [Line Items]                        
Net (loss) income                   $ (4,889,000) 24,015,000  
Effect of new accounting adoption       $ 255,000             $ 255,000  
Accounting Standards Update 2016-09 | Accumulated Deficit                        
Property, Plant and Equipment [Line Items]                        
Effect of new accounting adoption                   255,000    
ASU 2016-02 | Minimum | Adjustment                        
Property, Plant and Equipment [Line Items]                        
Right-to-use assets                   2,000,000    
Operating lease liability                   2,000,000    
ASU 2016-02 | Maximum | Adjustment                        
Property, Plant and Equipment [Line Items]                        
Right-to-use assets                   2,600,000    
Operating lease liability                   $ 2,600,000