v3.10.0.1
Document and Entity Information - shares
9 Months Ended
Sep. 29, 2018
Nov. 02, 2018
Document Documentand Entity Information [Abstract]    
Document Type 10-Q  
Amendment Flag false  
Document Period End Date Sep. 29, 2018  
Document Fiscal Year Focus 2018  
Document Fiscal Period Focus Q3  
Trading Symbol DNKN  
Entity Registrant Name DUNKIN' BRANDS GROUP, INC.  
Entity Central Index Key 0001357204  
Current Fiscal Year End Date --12-29  
Entity Filer Category Large Accelerated Filer  
Entity Emerging Growth Company false  
Entity Small Business false  
Entity Common Stock, Shares Outstanding   82,597,346