Property And Equipment (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Property, Plant and Equipment [Line Items]
Capitalized software development costs			$ 12.4
Total depreciation expense and amortization of capitalized software development costs	$ 4.7	$ 3.5	13.1	$ 9.4
Software And Software Development Costs [Member]
Property, Plant and Equipment [Line Items]
Amortization expense	3.0	$ 2.2	8.3	$ 6.5
Unamortized software development costs	$ 28.1		$ 28.1