Income Taxes (Details) $ in Millions	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2015 USD ($) Country	Sep. 30, 2014	Sep. 30, 2015 USD ($) Country	Sep. 30, 2014	Dec. 31, 2015	Dec. 31, 2014 USD ($)
Income Tax Disclosure [Abstract]
Effective income tax rate (as percent)	37.10%	35.50%	38.60%	37.90%
U.S. Federal statutory rate (as percent)	35.00%		35.00%
Gross unrecognized tax benefits, including interest and penalties	$ 32.7		$ 32.7			$ 30.8
Related tax benefits	1.4		1.4			1.4
Net unrecognized tax benefits	$ 31.3		$ 31.3			$ 29.4
Number of countries and territories in which the Company operates | Country	80		80
Forecast
Income Tax [Line Items]
Expected annual effective income tax rate (as percent)					38.00%