Restructuring Charges (Details) (USD $) In Millions, unless otherwise specified	9 Months Ended
	Sep. 30, 2014
Restructuring Cost and Reserve [Line Items]
Restructuring Cost, Total Expected Cost	$ 5.7
Restructuring Cost, Severance Costs	5.3
Restructuring Cost, Other Costs	0.4
Restructuring and Related Cost, Cost Incurred to Date	5.6
Restructuring and Related Costs, Cost Incurred to Date, Research and Development	4.9
Restructuring and Related Costs, Cost Incurred to Date, General and Administrative	0.7
Restructuring and Related Costs, Cost Incurred to Date, Stock-based Compensation	0.1
Restructuring Reserve	$ 0.4