Changes in Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014
Changes in Accumulated Other Comprehensive Income (Loss) [Roll Forward]
January 1	$ (618.2)	$ (191.6)
Other comprehensive income (loss) before reclassifications	(145.4)	92.3
Amounts reclassified from accumulated other comprehensive income (loss)	4.4	2.8
Other comprehensive income (loss)	(141.0)	95.1
June 30	(759.2)	(96.5)
Unrealized Gain (Loss) on Cash Flow Hedge
Changes in Accumulated Other Comprehensive Income (Loss) [Roll Forward]
January 1	0.0	0.0
Other comprehensive income (loss) before reclassifications	20.5	0.0
Amounts reclassified from accumulated other comprehensive income (loss)	0.0	0.0
Other comprehensive income (loss)	20.5	0.0
June 30	20.5	0.0
Unrealized Gain (Loss) on Available-for-Sale Securities
Changes in Accumulated Other Comprehensive Income (Loss) [Roll Forward]
January 1	(1.2)	(1.6)
Other comprehensive income (loss) before reclassifications	0.2	0.2
Amounts reclassified from accumulated other comprehensive income (loss)	0.0	0.0
Other comprehensive income (loss)	0.2	0.2
June 30	(1.0)	(1.4)
Defined Benefit Pension and Postemployment Plans
Changes in Accumulated Other Comprehensive Income (Loss) [Roll Forward]
January 1	(92.1)	(68.8)
Other comprehensive income (loss) before reclassifications	0.0	0.0
Amounts reclassified from accumulated other comprehensive income (loss)	4.4	2.8
Other comprehensive income (loss)	4.4	2.8
June 30	(87.7)	(66.0)
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	3.8	3.3
Actuarial (gains) losses	3.6	1.5
Net periodic benefit cost (see Note 8)	7.4	4.8
Income taxes	3.0	2.0
Periodic benefit cost, net of income taxes	4.4	2.8
Foreign Currency Translation
Changes in Accumulated Other Comprehensive Income (Loss) [Roll Forward]
January 1	(524.9)	(121.2)
Other comprehensive income (loss) before reclassifications	(166.1)	92.1
Amounts reclassified from accumulated other comprehensive income (loss)	0.0	0.0
Other comprehensive income (loss)	(166.1)	92.1
June 30	$ (691.0)	$ (29.1)