Segment Information (Sales By Major Product Group) (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 27, 2019	Jun. 28, 2019	Mar. 29, 2019	Dec. 31, 2018	Sep. 28, 2018	Jun. 29, 2018	Mar. 30, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Sales	$ 4,868.4	$ 4,378.0	$ 4,444.5	$ 4,220.2	$ 4,604.5	$ 4,173.6	$ 4,247.6	$ 4,022.8	$ 17,911.1	$ 17,048.5	$ 15,518.8
Analytical and physical instrumentation
Sales									2,463.8	2,437.0	2,232.9
Research and medical products
Sales									13,512.6	12,686.0	11,512.4
Product Identification
Sales									$ 1,934.7	$ 1,925.5	$ 1,773.5