Summary of Significant Accounting Policies (Capitalized Software and Hardware) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Property, Plant and Equipment
Amortization expense	$ 2.4	$ 1.4	$ 1.1
Prepaid Expenses and Other Current Assets
Property, Plant and Equipment
Capitalized software and hardware	2.0	1.2
Other Assets
Property, Plant and Equipment
Capitalized software and hardware	$ 5.0	$ 4.9
Minimum
Property, Plant and Equipment
Amortization period (in years)	1 year
Maximum
Property, Plant and Equipment
Amortization period (in years)	5 years