XML 14 R1.htm IDEA: XBRL DOCUMENT v3.19.2
Document and Entity Information - shares
 6 Months Ended
Jun. 29, 2019
Jul. 31, 2019
Document And Entity Information [Abstract]    
Document Type 10-Q  
Amendment Flag false  
Document Period End Date Jun. 29, 2019  
Document Fiscal Year Focus 2019  
Document Fiscal Period Focus Q2  
Trading Symbol WW  
Entity Registrant Name WEIGHT WATCHERS INTERNATIONAL INC  
Entity Central Index Key 0000105319  
Current Fiscal Year End Date --12-28  
Entity Filer Category Large Accelerated Filer  
Entity Small Business false  
Entity Emerging Growth Company false  
Entity Common Stock, Shares Outstanding   67,297,697
Entity Current Reporting Status Yes  
Entity Shell Company false  
Entity File Number 001-16769  
Entity Incorporation, State or Country Code VA  
Entity Tax Identification Number 11-6040273  
Entity Address, Address Line One 675 Avenue of the Americas  
Entity Address, Address Line Two 6th Floor  
Entity Address, City or Town New York  
Entity Address, State or Province NY  
Entity Address, Postal Zip Code 10010  
City Area Code (212)  
Local Phone Number 589-2700  
Title of 12(b) Security Common Stock  
Security Exchange Name NASDAQ  
Entity Interactive Data Current Yes  
Document Quarterly Report true  
Document Transition Report false