Annual report pursuant to Section 13 and 15(d)

Summary of Significant Accounting Policies (Details Textual)

v3.10.0.1
Summary of Significant Accounting Policies (Details Textual) - USD ($)
$ in Thousands
12 Months Ended
Dec. 29, 2018
Dec. 30, 2017
Dec. 31, 2016
Summary Of Significant Accounting Policies [Line Items]      
Contract asset, current $ 2,851    
Contract Liabilities, current 138    
Research and development costs charged to expense 14,122 $ 10,624 $ 4,334
Accounting Standards Update 2016-02 [Member]      
Summary Of Significant Accounting Policies [Line Items]      
Expected increase in lease assets due to new accounting pronouncements 14,000    
Expected increase in lease liabilities due to new accounting pronouncements $ 14,000    
Minimum [Member]      
Summary Of Significant Accounting Policies [Line Items]      
Finite-lived intangible assets, estimated useful life 1 year    
Minimum [Member] | Custom Products [Member]      
Summary Of Significant Accounting Policies [Line Items]      
Contract period for sale of product 3 months    
Minimum [Member] | Various Services [Member]      
Summary Of Significant Accounting Policies [Line Items]      
Service contracts period 3 months    
Maximum [Member]      
Summary Of Significant Accounting Policies [Line Items]      
Finite-lived intangible assets, estimated useful life 26 years    
Maximum [Member] | Custom Products [Member]      
Summary Of Significant Accounting Policies [Line Items]      
Contract period for sale of product 1 year    
Maximum [Member] | Various Services [Member]      
Summary Of Significant Accounting Policies [Line Items]      
Percentage of revenue 3.00%    
Service contracts period 1 year