Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Statement of Comprehensive Income [Abstract]
Net income	$ 103.5	$ 101.7	$ 262.5	$ 237.3
Other comprehensive income:
Foreign currency translation adjustments	10.2	(3.1)	39.4	11.3
Net change in pension and post-retirement liabilities	(2.7)	(0.4)	(8.1)	(4.5)
Reclassification of pension and post-retirement benefit losses into earnings	1.8	1.6	5.5	4.8
Change in fair value of available-for-sale marketable equity securities	0.1	(1.2)	0.2	(1.8)
Net change in fair value of cash flow hedges	3.4	2.0	10.5	1.4
Reclassification of cash flow hedge (gains) losses into earnings	(3.5)	2.4	(9.4)	10.6
Other comprehensive income before income taxes	9.3	1.3	38.1	21.8
Income tax benefit (expense)	0.1	(1.7)	0.0	(4.1)
Other comprehensive income, net of tax	9.4	(0.4)	38.1	17.7
Comprehensive income	$ 112.9	$ 101.3	$ 300.6	$ 255.0