Annual report pursuant to Section 13 and 15(d)

Revenue - Disaggregated by Product Lines (Details)

v3.10.0.1
Revenue - Disaggregated by Product Lines (Details) - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2018
Dec. 31, 2017
Dec. 31, 2016
Disaggregation of Revenue [Line Items]      
Sales $ 803,256 $ 624,464 $ 633,123
Aerospace      
Disaggregation of Revenue [Line Items]      
Sales 675,625 534,603 534,041
Test Systems      
Disaggregation of Revenue [Line Items]      
Sales 127,631 89,861 99,082
Electrical Power & Motion      
Disaggregation of Revenue [Line Items]      
Sales 303,180 264,286 288,465
Lighting & Safety      
Disaggregation of Revenue [Line Items]      
Sales 174,383 158,663 156,871
Avionics      
Disaggregation of Revenue [Line Items]      
Sales 131,849 53,960 32,761
Systems Certification      
Disaggregation of Revenue [Line Items]      
Sales 13,951 14,333 16,531
Structures      
Disaggregation of Revenue [Line Items]      
Sales 24,134 25,849 20,887
Other      
Disaggregation of Revenue [Line Items]      
Sales $ 28,128 $ 17,512 $ 18,526