Income Taxes (Details 3) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Income Taxes
Tax reserves related to current year uncertain tax positions	$ 6.0
Tax reserves related to prior year uncertain tax positions	5.2
Accrued interest related to prior year uncertain tax positions	8.0
Previously recorded tax reserves for uncertain tax positions that have settled and/or closed	0.4
Net tax expense in connection with uncertain tax positions	2.3
Tax positions that, if reversed, would affect the effective tax rate	11.5	21.3
Currency translation gains (losses) for foreign currency tax positions	2.5	1.8
Interest and penalties recognized, net of deferred taxes	1.2	0.7
Reductions in previously accrued interest and penalties	0.3
Prepaid Taxes	$ 32.3	$ 39.4