Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Statement of Comprehensive Income [Abstract]
Net income	$ 114.7	$ 108.0	$ 294.7	$ 283.4
Other comprehensive income:
Foreign currency translation adjustments	(6.2)	3.6	(2.4)	(9.4)
Reclassification of foreign currency translation adjustments into earnings	0.0	5.0	2.1	27.9
Net change in pension and post-retirement liabilities	7.6	(2.5)	10.1	(6.3)
Reclassification of pension and post-retirement benefit losses into earnings	1.5	2.4	4.4	7.0
non-cash pension settlement loss	0.0	0.0	60.6	0.0
Change in available-for-sale marketable equity securities	0.0	0.0	0.0	(1.8)
Net change in fair value of cash flow hedges	(3.1)	(3.8)	(2.3)	(8.9)
Reclassification of cash flow hedge losses (gains) into earnings	2.5	(0.3)	6.9	(7.3)
Other comprehensive income (loss) before income taxes	2.3	4.4	79.4	1.2
Income tax expense (benefit)	0.1	1.0	(17.8)	(19.4)
Other comprehensive income (loss), net of tax	2.4	5.4	61.6	(18.2)
Comprehensive income	$ 117.1	$ 113.4	$ 356.3	$ 265.2