Document and Entity Information - shares
9 Months Ended
Sep. 28, 2019
Oct. 26, 2019
Entity Information [Line Items]    
Document Type 10-Q  
Document Period End Date Sep. 28, 2019  
Document Quarterly Report true  
Document Transition Report false  
Entity Central Index Key 0001159167  
Entity File Number 001-36414  
Entity Registrant Name iROBOT CORPORATION  
Entity Incorporation, State or Country Code DE  
Entity Tax Identification Number 77-0259335  
Amendment Flag false  
Entity Address, Address Line One 8 Crosby Drive  
Entity Address, City or Town Bedford  
Entity Address, State or Province MA  
Entity Address, Postal Zip Code 01730  
City Area Code 781  
Local Phone Number 430-3000  
Title of 12(b) Security Common Stock, $0.01 par value  
Trading Symbol IRBT  
Security Exchange Name NASDAQ  
Document Fiscal Year Focus 2019  
Document Fiscal Period Focus Q3  
Current Fiscal Year End Date --12-28  
Entity Shell Company false  
Entity Small Business false  
Entity Emerging Growth Company false  
Entity Current Reporting Status Yes  
Entity Interactive Data Current Yes  
Entity Filer Category Large Accelerated Filer  
Entity Common Stock, Shares Outstanding   28,270,544