Income Taxes (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Dec. 31, 2014
Income Tax Contingency [Line Items]
Effective income tax (percent)	39.90%	37.50%	39.90%	39.10%
Gross unrecognized tax benefits	$ 33.2		$ 33.2		$ 32.9
Accrued interest and penalties on unrecognized tax benefits	17.5		17.5		$ 17.3
Possible decrease in unrecognized tax benefits	$ 15.0		$ 15.0
Minimum
Income Tax Contingency [Line Items]
Income tax years under examination			2004
Maximum
Income Tax Contingency [Line Items]
Income tax years under examination			2015