Annual report pursuant to Section 13 and 15(d)

Nature of Business and Basis of Presentation - Additional Information (Detail)

v2.4.0.8
Nature of Business and Basis of Presentation - Additional Information (Detail) (USD $)
Dec. 31, 2013
Dec. 31, 2012
Organization Consolidation And Presentation Of Financial Statements [Abstract]    
Accumulated deficit $ (133,689,000) $ (101,840,000)
Cash equivalents and short-term investments $ 39,200,000