Segment Information - Narrative (Details)	6 Months Ended
	Jun. 28, 2020 product_line segment
Revenue from External Customer [Line Items]
Number of reportable segments | segment	4
Instrumentation
Revenue from External Customer [Line Items]
Number of product lines	3
Digital Imaging
Revenue from External Customer [Line Items]
Number of product lines	1
Aerospace and Defense Electronics
Revenue from External Customer [Line Items]
Number of product lines	1
Engineered Systems
Revenue from External Customer [Line Items]
Number of product lines	1