Reportable Business Segments, Segment Results (Details) $ in Millions	3 Months Ended
	Mar. 31, 2021 USD ($) segment	Mar. 31, 2020 USD ($)
Segment reporting information
Number of reportable business segments | segment	2
Net sales	$ 2,377.1	$ 1,862.0
Operating income	464.8	316.9
Interconnect Products and Assemblies
Segment reporting information
Net sales	2,280.0	1,779.0
Cable Products and Solutions
Segment reporting information
Net sales	97.1	83.0
Operating Segment
Segment reporting information
Net sales	2,377.1	1,862.0
Operating income	497.9	346.1
Operating Segment | Interconnect Products and Assemblies
Segment reporting information
Net sales	2,280.0	1,779.0
Operating income	489.4	339.8
Operating Segment | Cable Products and Solutions
Segment reporting information
Net sales	97.1	83.0
Operating income	8.5	6.3
Operating Segment | Corporate and Other
Segment reporting information
Net sales	0.0	0.0
Inter-Segment
Segment reporting information
Net sales	29.5	17.3
Inter-Segment | Interconnect Products and Assemblies
Segment reporting information
Net sales	17.8	8.4
Inter-Segment | Cable Products and Solutions
Segment reporting information
Net sales	11.7	8.9
Inter-Segment | Corporate and Other
Segment reporting information
Net sales	$ 0.0	$ 0.0