Annual report pursuant to Section 13 and 15(d)

Summary of Significant Accounting Policies (Details Textual)

v3.20.4
Summary of Significant Accounting Policies (Details Textual) - USD ($)
$ in Thousands
12 Months Ended
Jan. 02, 2021
Dec. 28, 2019
Dec. 29, 2018
Dec. 31, 2018
Summary Of Significant Accounting Policies [Line Items]        
Right-of-use assets $ 16,616 $ 12,310    
Retained earnings 270,320 267,658    
Long-lived asset impairment 0      
Contract asset, current 2,776 2,796    
Contract Liabilities, current 4,208 353    
Research and development costs charged to expense $ 15,557 15,163 $ 14,122  
Restructuring charges   1,724    
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 5.00%      
Service contracts period 1 year      
Total Liabilities [Member]        
Summary Of Significant Accounting Policies [Line Items]        
Lease liabilities $ 17,464 $ 12,467    
ASU 2016-02        
Summary Of Significant Accounting Policies [Line Items]        
Right-of-use assets       $ 13,900
Retained earnings       134
ASU 2016-02 | Total Liabilities [Member]        
Summary Of Significant Accounting Policies [Line Items]        
Lease liabilities       $ 13,900