Document and Entity Information
12 Months Ended
Dec. 31, 2011
Document And Entity Information [Abstract]  
Document Type 20-F
Amendment Flag false
Document Period End Date Dec. 31, 2011
Entity Registrant Name Allot Communications Ltd.
Entity Central Index Key 0001365767
Current Fiscal Year End Date --12-31
Document Fiscal Period Focus FY
Document Fiscal Year Focus 2011
Entity Filer Category Accelerated Filer
Entity Common Stock, Shares Outstanding 30,950,234
Entity Current Reporting Status Yes
Entity Well-known Seasoned Issuer No