Accumulated Other Comprehensive Income (Loss) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Changes to accumulated other comprehensive income (loss)
Balance at the beginning of the period	$ (159.8)	$ (42.6)
Unrealized gain	0.1	0.1
Reclassification to earnings	1.3	0.4
Gain (loss) arising during period		2.7
Effect of exchange rate changes and deferred taxes	(81.9)	(12.6)
Balance at the end of the period	(240.3)	(52.0)
Foreign Currency Translation Adjustment
Changes to accumulated other comprehensive income (loss)
Balance at the beginning of the period	(40.5)	31.9
Effect of exchange rate changes and deferred taxes	(86.3)	(16.9)
Balance at the end of the period	(126.8)	15.0
Unrealized Gain (Loss) on Securities
Changes to accumulated other comprehensive income (loss)
Balance at the beginning of the period	0.8	0.6
Unrealized gain	0.1	0.1
Reclassification to earnings	(0.1)	(0.1)
Effect of exchange rate changes and deferred taxes	0	0.1
Balance at the end of the period	0.8	0.7
Unrealized Gain (Loss) on Derivatives
Changes to accumulated other comprehensive income (loss)
Balance at the beginning of the period	4.7	6.5
Unrealized gain	0	0
Reclassification to earnings	0
Effect of exchange rate changes and deferred taxes	0	0
Balance at the end of the period	4.7	6.5
Defined Benefit Plans
Changes to accumulated other comprehensive income (loss)
Balance at the beginning of the period	(124.8)	(81.6)
Reclassification to earnings	1.4	0.5
Gain (loss) arising during period		2.7
Effect of exchange rate changes and deferred taxes	4.4	4.2
Balance at the end of the period	$ (119.0)	$ (74.2)