v2.4.0.6
Document and Entity Information
9 Months Ended
Sep. 30, 2013
Oct. 10, 2013
Class A common stock
Oct. 10, 2013
Class B common stock
Entity Registrant Name IRONWOOD PHARMACEUTICALS INC    
Entity Central Index Key 0001446847    
Document Type 10-Q    
Document Period End Date Sep. 30, 2013    
Amendment Flag false    
Current Fiscal Year End Date --12-31    
Entity Current Reporting Status Yes    
Entity Filer Category Large Accelerated Filer    
Entity Common Stock, Shares Outstanding   97,477,669 23,425,910
Document Fiscal Year Focus 2013    
Document Fiscal Period Focus Q3