Document And Entity Information - USD ($)
12 Months Ended
Dec. 27, 2018
Feb. 22, 2019
Document And Entity Information [Abstract]    
Document Type 10-K  
Amendment Flag false  
Document Period End Date Dec. 27, 2018  
Document Fiscal Year Focus 2018  
Document Fiscal Period Focus FY  
Entity Registrant Name National CineMedia, LLC  
Entity Central Index Key 0001527190  
Entity Filer Category Non-accelerated Filer  
Current Fiscal Year End Date --12-27  
Entity Current Reporting Status Yes  
Entity Voluntary Filers Yes  
Entity Well-known Seasoned Issuer No  
Entity Public Float $ 0  
Entity Common Stock, Shares Outstanding   157,637,220