Goodwill and Intangible Assets - Changes in Carrying Amount of Goodwill by Segment (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Dec. 31, 2018
Goodwill
Goodwill	$ 2,238.0	$ 2,229.2
Accumulated impairment losses	(46.6)	(46.6)
Goodwill
Beginning balance	2,182.6
Foreign currency translation and other	8.8
Ending balance	2,191.4
Electronics
Goodwill
Goodwill	1,232.7	1,226.7
Accumulated impairment losses	0.0	0.0
Goodwill
Beginning balance	1,226.7
Foreign currency translation and other	6.0
Ending balance	1,232.7
Industrial & Specialty
Goodwill
Goodwill	1,005.3	1,002.5
Accumulated impairment losses	(46.6)	$ (46.6)
Goodwill
Beginning balance	955.9
Foreign currency translation and other	2.8
Ending balance	$ 958.7