Income Taxes - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Income Tax Disclosure [Abstract]
Provision for income taxes	$ 27.0	$ 22.9	$ 39.9	$ 45.7
Effective tax rate (as a percent)	30.60%	31.30%	23.60%	31.30%
Effective tax rate excluding discrete benefits (as a percent)			30.50%
Benefits primarily related to the release of reserves for uncertain tax positions			$ 11.6