Accumulated Other Comprehensive Loss, Net of Tax Changes in AOCI (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Accumulated Other Comprehensive Income (Loss) [Line Items]
Available-for-sale securities, before reclassifications	$ 0.0	$ 0.0	$ 0.5
Total other comprehensive income, before reclassifications	(135.4)	122.5
Total reclassification from AOCI	22.1	14.1	8.1
Accumulated other comprehensive loss, net of tax	(941.1)	(827.8)	(964.4)
Foreign Currency Translation Adjustment
Accumulated Other Comprehensive Income (Loss) [Line Items]
Foreign currency translation adjustment, before reclassifications	(146.8)	132.2
Foreign currency translation adjustment, amount reclassified from AOCI, net of tax	15.7	1.1
Foreign currency translation adjustment, net of tax	(716.4)	(585.3)	(718.6)
Available-for-sale Securities
Accumulated Other Comprehensive Income (Loss) [Line Items]
Available-for-sale securities, before reclassifications	0.0	0.0
Available-for-sale securities, amount reclassified from AOCI, net of tax	0.0	(0.6)
Available-for-sale securities adjustment, net of tax	0.0	0.0	0.6
Derivative Instruments
Accumulated Other Comprehensive Income (Loss) [Line Items]
Derivative instruments, before reclassifications	0.0	0.0
Derivative instruments, amount reclassified from AOCI, net of tax	1.5	1.6
Derivative Instruments, net of tax	(5.3)	(6.8)	(8.4)
Defined Benefit and Postretirement Plans
Accumulated Other Comprehensive Income (Loss) [Line Items]
Defined Benefit and Postretirement Plans, before reclassifications	11.4	(9.7)
Defined benefit and Postretirement Plans, amount reclassified from AOCI, net of tax	4.9	12.0
Pension and Other Postretirement Benefit Plans, net of tax	$ (219.4)	$ (235.7)	$ (238.0)