Goodwill and Other Intangible Assets - Carrying Amount of Goodwill (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Goodwill [Line Items]
Gross goodwill		$ 217,779
Accumulated goodwill impairment		(81,722)
Goodwill [Roll Forward]
Goodwill, beginning balance	$ 136,057
Goodwill from acquisition during the period	34,860
Goodwill, ending balance	170,917
Electronic Systems
Goodwill [Line Items]
Gross goodwill		199,157
Accumulated goodwill impairment		(81,722)
Goodwill [Roll Forward]
Goodwill, beginning balance	117,435
Goodwill from acquisition during the period	0
Goodwill, ending balance	117,435
Structural Systems
Goodwill [Line Items]
Gross goodwill		18,622
Accumulated goodwill impairment		$ 0
Goodwill [Roll Forward]
Goodwill, beginning balance	18,622
Goodwill from acquisition during the period	34,860
Goodwill, ending balance	$ 53,482