Document and Entity Information - USD ($)
$ in Millions
12 Months Ended
Dec. 26, 2018
Feb. 28, 2019
Jun. 27, 2018
Document And Entity Information [Abstract]      
Document Type 10-K    
Amendment Flag false    
Document Period End Date Dec. 26, 2018    
Document Fiscal Year Focus 2018    
Document Fiscal Period Focus FY    
Trading Symbol LOCO    
Entity Registrant Name El Pollo Loco Holdings, Inc.    
Entity Central Index Key 0001606366    
Entity Central Index Key --12-26    
Entity Well-known Seasoned Issuer No    
Entity Current Reporting Status Yes    
Entity Voluntary Filers No    
Entity Filer Category Accelerated Filer    
Emerging Growth Company true    
Small Business Entity false    
Entity Ex Transition Period true    
Shell Company false    
Entity Common Stock, Shares Outstanding   38,962,766  
Entity Public Float     $ 245