Annual report pursuant to Section 13 and 15(d)

Document and Entity Information

v2.4.0.8
Document and Entity Information (USD $)
12 Months Ended
Dec. 31, 2013
Feb. 28, 2014
Jun. 30, 2013
Document And Entity Information [Abstract]      
Document Type 10-K    
Amendment Flag false    
Document Period End Date Dec. 31, 2013    
Document Fiscal Year Focus 2013    
Document Fiscal Period Focus FY    
Trading Symbol THLD    
Entity Registrant Name THRESHOLD PHARMACEUTICALS INC    
Entity Central Index Key 0001183765    
Current Fiscal Year End Date --12-31    
Entity Well-known Seasoned Issuer No    
Entity Current Reporting Status Yes    
Entity Voluntary Filers No    
Entity Filer Category Accelerated Filer    
Entity Common Stock, Shares Outstanding   59,345,804  
Entity Public Float     $ 263,301,745