Nature of Business and Accounting Policies (Details 3) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Foreign Currency Translation
Foreign currency translation adjustment, net of tax	$ 0.7	$ 0.9	$ 1.1
Foreign currency transaction gain (loss), before tax	$ 0.4	$ (0.7)	$ (0.1)
Furniture and equipment
Property and Equipment
Property and equipment useful life, minimum (in years)	4
Property and equipment useful life, maximum (in years)	7
Computers and software
Property and Equipment
Property and equipment useful life, minimum (in years)	3
Property and equipment useful life, maximum (in years)	5