Changes in Accumulated Other Comprehensive Income (Loss) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Changes in Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Balance January 1, 2013	$ (191.6)	$ (129.5)
Other comprehensive income before reclassifications	20.5	(172.6)
Amounts reclassified from accumulated other comprehensive income (loss)	1.4	1.7
Other comprehensive income	21.9	(170.9)
Balance March 31, 2013	(169.7)	(300.4)
Unrealized Gain (Loss) on Available-for-Sale Securities
Changes in Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Balance January 1, 2013	(1.6)	(2.0)
Other comprehensive income before reclassifications	0.1	0.2
Amounts reclassified from accumulated other comprehensive income (loss)	0	0
Other comprehensive income	0.1	0.2
Balance March 31, 2013	(1.5)	(1.8)
Defined Benefit Pension and Postemployment Plans
Changes in Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Balance January 1, 2013	(68.8)	(89.8)
Other comprehensive income before reclassifications	0	0
Amounts reclassified from accumulated other comprehensive income (loss)	1.4	1.7
Other comprehensive income	1.4	1.7
Balance March 31, 2013	(67.4)	(88.1)
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	1.6	1.4
Actuarial (gains) losses	0.7	1.6
Net periodic benefit cost (see Note 9)	2.3	3.0
Income tax expense	0.9	1.3
Net of tax	1.4	1.7
Foreign Currency Translation
Changes in Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Balance January 1, 2013	(121.2)	(37.7)
Other comprehensive income before reclassifications	20.4	(172.8)
Amounts reclassified from accumulated other comprehensive income (loss)	0	0
Other comprehensive income	20.4	(172.8)
Balance March 31, 2013	$ (100.8)	$ (210.5)