Business Segment Information - Segment Assets (Detail) - USD ($) $ in Thousands	Apr. 01, 2017	Dec. 31, 2016
Segment Reporting Information [Line Items]
Total Assets	$ 517,971	$ 515,429
Total Goodwill and Intangibles	181,918	184,127
Operating Segments | Structural Systems
Segment Reporting Information [Line Items]
Total Assets	185,073	175,580
Total Goodwill and Intangibles	3,517	3,745
Operating Segments | Electronic Systems
Segment Reporting Information [Line Items]
Total Assets	319,924	325,780
Total Goodwill and Intangibles	178,401	180,382
Corporate Administration
Segment Reporting Information [Line Items]
Total Assets	$ 12,974	$ 14,069