Segment Information (Narrative) (Details) $ in Millions	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2018 USD ($) product_line	Oct. 01, 2017 USD ($)	Sep. 30, 2018 USD ($) segment product_line	Oct. 01, 2017 USD ($)	Dec. 31, 2017 USD ($)
Revenue from External Customer [Line Items]
Number of reportable segments | segment			4
Net sales	$ 725.3	$ 662.2	$ 2,153.4	$ 1,899.4
Aerospace and Defense Electronics
Revenue from External Customer [Line Items]
Net sales	$ 171.1		$ 518.2
Number of Product Lines | product_line	1		1
Engineered Systems
Revenue from External Customer [Line Items]
Net sales	$ 75.0		$ 218.1
Instrumentation
Revenue from External Customer [Line Items]
Net sales	$ 256.2		$ 757.8
Number of Product Lines | product_line	3		3
Digital Imaging
Revenue from External Customer [Line Items]
Net sales	$ 223.0		$ 659.3
Microwave Products
Revenue from External Customer [Line Items]
Net sales					$ 24.2