Document and Entity Information - USD ($)
12 Months Ended
Dec. 29, 2018
Jan. 31, 2019
Jun. 29, 2018
Dec. 30, 2017
Document and Entity Information [Abstract]        
Common Stock, Shares, Outstanding 27,788,272     27,945,144
Entity Registrant Name IROBOT CORP      
Entity Central Index Key 0001159167      
Document Type 10-K      
Document Period End Date Dec. 29, 2018      
Amendment Flag false      
Document Fiscal Year Focus 2018      
Document Fiscal Period Focus FY      
Current Fiscal Year End Date --12-29      
Entity Well-known Seasoned Issuer Yes      
Entity Voluntary Filers No      
Entity Current Reporting Status Yes      
Entity Filer Category Large Accelerated Filer      
Entity Small Business false      
Entity Emerging Growth Company false      
Entity Shell Company false      
Entity Public Float     $ 2,000,000,000  
Entity Common Stock, Shares Outstanding   27,796,614