Reportable Business Segments, Segment Results (Details) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020 USD ($)	Sep. 30, 2019 USD ($)	Sep. 30, 2020 USD ($) segment	Sep. 30, 2019 USD ($)
Segment reporting information
Number of reportable business segments | segment			2
Net sales	$ 2,323.4	$ 2,100.6	$ 6,172.9	$ 6,074.4
Operating income	475.8	413.6	1,150.1	1,189.4
Interconnect Products and Assemblies
Segment reporting information
Net sales	2,221.9	2,000.8	5,899.4	5,789.0
Cable Products and Solutions
Segment reporting information
Net sales	101.5	99.8	273.5	285.4
Operating Segment
Segment reporting information
Net sales	2,323.4	2,100.6	6,172.9	6,074.4
Operating income	509.3	444.1	1,243.3	1,301.7
Operating Segment | Interconnect Products and Assemblies
Segment reporting information
Net sales	2,221.9	2,000.8	5,899.4	5,789.0
Operating income	498.4	433.9	1,217.6	1,272.4
Operating Segment | Cable Products and Solutions
Segment reporting information
Net sales	101.5	99.8	273.5	285.4
Operating income	10.9	10.2	25.7	29.3
Operating Segment | Corporate and Other
Segment reporting information
Net sales	0.0	0.0	0.0	0.0
Inter-Segment
Segment reporting information
Net sales	28.0	23.6	66.7	63.7
Inter-Segment | Interconnect Products and Assemblies
Segment reporting information
Net sales	18.4	11.9	39.4	22.9
Inter-Segment | Cable Products and Solutions
Segment reporting information
Net sales	9.6	11.7	27.3	40.8
Inter-Segment | Corporate and Other
Segment reporting information
Net sales	$ 0.0	$ 0.0	$ 0.0	$ 0.0