XML 31 R1.htm IDEA: XBRL DOCUMENT v2.4.0.6
Document and Entity Information (USD $)
 9 Months Ended
Dec. 31, 2011
Mar. 06, 2012
Sep. 30, 2011
Document Type 10-K    
Amendment Flag false    
Document Period End Date Dec. 31, 2011    
Document Fiscal Year Focus 2011    
Document Fiscal Period Focus FY    
Trading Symbol RGEN    
Entity Registrant Name REPLIGEN CORP    
Entity Central Index Key 0000730272    
Current Fiscal Year End Date --12-31    
Entity Well-known Seasoned Issuer No    
Entity Current Reporting Status No    
Entity Voluntary Filers No    
Entity Filer Category Accelerated Filer    
Entity Common Stock, Shares Outstanding   30,724,757  
Entity Public Float     $ 100,130,108