Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014
Income Tax Disclosure [Abstract]
Net unrecognized tax benefit	$ 44.0		$ 44.0		$ 66.9
Income tax interest and penalties accrued	0.3		0.3
Net tax benefit recognized due to settlement of tax issues	20.3
Deferred tax assets	121.3		$ 121.3
Valuation Allowance, Deferred Tax Asset, Explanation of Change	$ 3.8
Effective tax rate	6.70%	(3.90%)	9.70%	9.00%
U.S. federal statutory rate			35.00%