Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended			9 Months Ended
	Sep. 30, 2015	Jun. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Dec. 31, 2014
Income Tax Disclosure [Abstract]
Net unrecognized tax benefit	$ 48.3			$ 48.3		$ 66.9
Income tax interest and penalties accrued	0.5			0.5
Net tax benefit recognized due to settlement of tax issues		$ 20.3
Deferred tax assets	$ 152.0			$ 152.0
Effective tax rate	(4.80%)		1.40%	5.80%	6.90%
U.S. federal statutory rate				35.00%