Changes in Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Changes in Accumulated Other Comprehensive Income (Loss) [Roll Forward]
January 1	$ (1,015.4)	$ (618.2)
Other comprehensive income (loss) before reclassifications	63.8	(320.7)
Amounts reclassified (to) from accumulated other comprehensive income (loss)	2.3	2.2
Other comprehensive income (loss)	66.1	(318.5)
March 31	(949.3)	(936.7)
Unamortized Loss on Cash Flow Hedge
Changes in Accumulated Other Comprehensive Income (Loss) [Roll Forward]
January 1	(3.3)	0.0
Other comprehensive income (loss) before reclassifications	(28.5)	(2.5)
Amounts reclassified (to) from accumulated other comprehensive income (loss)	0.0	0.0
Other comprehensive income (loss)	(28.5)	(2.5)
March 31	(31.8)	(2.5)
Accumulated other comprehensive loss, before tax	54.5
Unrealized Loss on Available-for-Sale Securities
Changes in Accumulated Other Comprehensive Income (Loss) [Roll Forward]
January 1	(0.9)	(1.2)
Other comprehensive income (loss) before reclassifications	0.0	0.2
Amounts reclassified (to) from accumulated other comprehensive income (loss)	0.0	0.0
Other comprehensive income (loss)	0.0	0.2
March 31	(0.9)	(1.0)
Defined Benefit Pension and Postemployment Plans
Changes in Accumulated Other Comprehensive Income (Loss) [Roll Forward]
January 1	(87.9)	(92.1)
Other comprehensive income (loss) before reclassifications	0.0	0.0
Amounts reclassified (to) from accumulated other comprehensive income (loss)	2.3	2.2
Other comprehensive income (loss)	2.3	2.2
March 31	(85.6)	(89.9)
Defined Benefit Pension and Postemployment Plans | Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification out of Accumulated Other Comprehensive Income [Abstract]
Prior service cost	1.8	1.9
Actuarial (gains) losses	1.5	1.8
Net periodic benefit cost (see Note 8)	3.3	3.7
Income taxes	1.0	1.5
Periodic benefit cost, net of income tax	2.3	2.2
Foreign Currency Translation
Changes in Accumulated Other Comprehensive Income (Loss) [Roll Forward]
January 1	(923.3)	(524.9)
Other comprehensive income (loss) before reclassifications	92.3	(318.4)
Amounts reclassified (to) from accumulated other comprehensive income (loss)	0.0	0.0
Other comprehensive income (loss)	92.3	(318.4)
March 31	$ (831.0)	$ (843.3)