Summary of Significant Accounting Policies - Disaggregated Revenue (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 29, 2019	Jun. 30, 2018	Jun. 29, 2019	Jun. 30, 2018
Disaggregation of Revenue [Line Items]
Net Revenues	$ 180,495	$ 154,827	$ 353,061	$ 305,282
Military and space
Disaggregation of Revenue [Line Items]
Net Revenues	77,189	70,326	150,886	136,681
Commercial Aerospace
Disaggregation of Revenue [Line Items]
Net Revenues	91,988	71,844	180,456	142,676
Industrial
Disaggregation of Revenue [Line Items]
Net Revenues	11,318	12,657	21,719	25,925
Electronic Systems
Disaggregation of Revenue [Line Items]
Net Revenues	89,260	84,502	173,457	166,910
Electronic Systems | Military and space
Disaggregation of Revenue [Line Items]
Net Revenues	60,272	54,368	117,704	106,901
Electronic Systems | Commercial Aerospace
Disaggregation of Revenue [Line Items]
Net Revenues	17,670	17,477	34,034	34,084
Electronic Systems | Industrial
Disaggregation of Revenue [Line Items]
Net Revenues	11,318	12,657	21,719	25,925
Structural Systems
Disaggregation of Revenue [Line Items]
Net Revenues	91,235	70,325	179,604	138,372
Structural Systems | Military and space
Disaggregation of Revenue [Line Items]
Net Revenues	16,917	15,958	33,182	29,780
Structural Systems | Commercial Aerospace
Disaggregation of Revenue [Line Items]
Net Revenues	$ 74,318	$ 54,367	$ 146,422	$ 108,592