Quarterly report pursuant to Section 13 or 15(d)

Note 4 - Interim Consolidated Financial Statement Details (Details Textual)

v3.19.3
Note 4 - Interim Consolidated Financial Statement Details (Details Textual) - USD ($)
 3 Months Ended 9 Months Ended
Sep. 29, 2019
Mar. 31, 2019
Sep. 30, 2018
Sep. 29, 2019
Sep. 30, 2018
Dec. 31, 2018
Dec. 30, 2018
Accounts Receivable, Allowance for Credit Loss, Period Increase (Decrease), Total       $ 1,447,000      
Restructuring Charges, Total $ 6,454,000   $ 58,000 8,624,000 $ 154,000    
Depreciation, Total       4,902,000 2,426,000    
Amortization of Intangible Assets, Total 1,844,000     5,532,000    
Goodwill, Ending Balance 18,165,000     18,165,000     $ 18,165,000
Business Combination, Contingent Consideration, Liability, Total   $ 0          
Business Combination, Contingent Consideration Arrangements, Change in Amount of Contingent Consideration, Liability $ (3,050,000) (3,050,000)    
Amortization of Debt Issuance Costs       1,300,000 34,000    
Term Loan B [Member] | TCW Asset Management Company, LLC [Member]              
Amortization of Debt Issuance Costs 477,000            
Machinery and Equipment [Member]              
Capital Leased Assets, Gross, Total 2,275,000     2,275,000     2,275,000
Capital Leases, Lessee Balance Sheet, Assets by Major Class, Accumulated Depreciation 834,000     834,000     409,000
Machinery and Equipment [Member] | Assets Under Capital Lease [Member]              
Depreciation, Total 142,000   34,000 426,000 70,000    
Building and Building Improvements [Member]              
Capital Leased Assets, Gross, Total 9,082,000     9,082,000     9,082,000
Capital Leases, Lessee Balance Sheet, Assets by Major Class, Accumulated Depreciation 699,000     699,000     96,000
Building and Building Improvements [Member] | Assets Under Capital Lease [Member]              
Depreciation, Total 201,000   603,000    
Furniture and Fixtures [Member]              
Capital Leased Assets, Gross, Total 297,000     297,000   $ 297,000  
Capital Leases, Lessee Balance Sheet, Assets by Major Class, Accumulated Depreciation 35,000     35,000    
Furniture and Fixtures [Member] | Assets Under Capital Lease [Member]              
Depreciation, Total 9,000   29,000    
SEC Schedule, 12-09, Reserve, Inventory [Member]              
SEC Schedule, 12-09, Valuation Allowances and Reserves, Period Increase (Decrease), Total       1,350,000      
Dongguan Facility Closure [Member]              
Restructuring Charges, Total 5,539,000   5,539,000    
Dongguan Facility Closure [Member] | Machinery and Equipment [Member]              
Property, Plant and Equipment, Transfers and Changes 883,000            
Accumulated Depreciation, Depletion and Amortization, Write Down 754,000            
Dongguan Facility Closure [Member] | Furniture and Fixtures [Member]              
Property, Plant and Equipment, Transfers and Changes 35,000            
Accumulated Depreciation, Depletion and Amortization, Write Down 25,000            
Dongguan Facility Closure [Member] | Computer Hardware And Software [Member]              
Property, Plant and Equipment, Transfers and Changes 252,000            
Accumulated Depreciation, Depletion and Amortization, Write Down 213,000            
Dongguan Facility Closure [Member] | Leasehold Improvements [Member]              
Property, Plant and Equipment, Transfers and Changes 111,000            
Accumulated Depreciation, Depletion and Amortization, Write Down 28,000            
Dongguan Facility Closure [Member] | Restructuring Charges Related to Allowance for Doubtful Accounts Receivable [Member]              
Restructuring Charges, Total 1,691,000   1,691,000    
Dongguan Facility Closure [Member] | Restructuring Charges Related to Provision for Obsolete Raw Material Inventories [Member]              
Restructuring Charges, Total 1,550,000   1,550,000    
Dongguan Facility Closure [Member] | Restructuring Charges Related to Write Down of Property, Plant and Equipment [Member]              
Restructuring Charges, Total 261,000   $ 261,000    
Dongguan Facility Closure [Member] | Restructuring Charges Related to Write Down of Property, Plant and Equipment [Member] | Machinery and Equipment [Member]              
Restructuring Charges, Total 129,000            
Dongguan Facility Closure [Member] | Restructuring Charges Related to Write Down of Property, Plant and Equipment [Member] | Furniture and Fixtures [Member]              
Restructuring Charges, Total 10,000            
Dongguan Facility Closure [Member] | Restructuring Charges Related to Write Down of Property, Plant and Equipment [Member] | Computer Hardware And Software [Member]              
Restructuring Charges, Total 39,000            
Dongguan Facility Closure [Member] | Restructuring Charges Related to Write Down of Property, Plant and Equipment [Member] | Leasehold Improvements [Member]              
Restructuring Charges, Total $ 83,000