Annual report pursuant to Section 13 and 15(d)

REVENUE - Disaggregated by Product Lines (Details)

v3.22.0.1
REVENUE - Disaggregated by Product Lines (Details) - USD ($)
$ in Thousands
 3 Months Ended 12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Disaggregation of Revenue [Line Items]          
Sales $ 116,052 $ 114,803 $ 444,908 $ 502,587 $ 772,702
Aerospace          
Disaggregation of Revenue [Line Items]          
Sales     365,238 417,988 692,609
Test Systems          
Disaggregation of Revenue [Line Items]          
Sales     79,670 84,599 80,093
Electrical Power & Motion          
Disaggregation of Revenue [Line Items]          
Sales     141,746 179,245 338,237
Lighting & Safety          
Disaggregation of Revenue [Line Items]          
Sales     103,749 118,928 185,462
Avionics          
Disaggregation of Revenue [Line Items]          
Sales     64,901 76,113 106,787
Systems Certification          
Disaggregation of Revenue [Line Items]          
Sales     13,050 6,899 14,401
Structures          
Disaggregation of Revenue [Line Items]          
Sales     5,529 9,832 23,117
Other          
Disaggregation of Revenue [Line Items]          
Sales     $ 36,263 $ 26,971 $ 24,605