Summary Of Significant Accounting Policies - Estimated Useful Lives of Property and Equipment (Detail)	12 Months Ended
	Dec. 31, 2013
Laboratory equipment [Member]
Property, Plant and Equipment [Line Items]
Property and Equipment, Estimated Useful Life, years	5 years
Minimum [Member] | Furniture and fixtures [Member]
Property, Plant and Equipment [Line Items]
Property and Equipment, Estimated Useful Life, years	3 years
Minimum [Member] | Computer equipment and software [Member]
Property, Plant and Equipment [Line Items]
Property and Equipment, Estimated Useful Life, years	3 years
Maximum [Member] | Furniture and fixtures [Member]
Property, Plant and Equipment [Line Items]
Property and Equipment, Estimated Useful Life, years	5 years
Maximum [Member] | Computer equipment and software [Member]
Property, Plant and Equipment [Line Items]
Property and Equipment, Estimated Useful Life, years	5 years