Quarterly report pursuant to Section 13 or 15(d)

Revenue - Disaggregated by Product Lines (Details)

v3.20.1
Revenue - Disaggregated by Product Lines (Details) - USD ($)
$ in Thousands
3 Months Ended
Mar. 28, 2020
Mar. 30, 2019
Disaggregation of Revenue [Line Items]    
Sales $ 157,584 $ 208,174
Aerospace Segment    
Disaggregation of Revenue [Line Items]    
Sales 141,070 188,501
Test Systems Segment    
Disaggregation of Revenue [Line Items]    
Sales 16,514 19,673
Electrical Power & Motion    
Disaggregation of Revenue [Line Items]    
Sales 69,456 92,537
Lighting & Safety    
Disaggregation of Revenue [Line Items]    
Sales 37,922 48,605
Avionics    
Disaggregation of Revenue [Line Items]    
Sales 22,143 33,861
Systems Certification    
Disaggregation of Revenue [Line Items]    
Sales 3,331 1,618
Structures    
Disaggregation of Revenue [Line Items]    
Sales 3,042 5,947
Other    
Disaggregation of Revenue [Line Items]    
Sales $ 5,176 $ 5,933