v3.10.0.1
Document And Entity Information - USD ($)
$ in Billions
9 Months Ended
Sep. 30, 2018
Oct. 26, 2018
Jun. 30, 2017
Document And Entity Information [Abstract]      
Entity Registrant Name HollyFrontier Corp    
Entity Central Index Key 0000048039    
Current Fiscal Year End Date --12-31    
Entity Filer Category Large Accelerated Filer    
Document Type 10-Q    
Document Period End Date Sep. 30, 2018    
Document Fiscal Year Focus 2018    
Document Fiscal Period Focus Q3    
Amendment Flag false    
Entity Small Business false    
Entity Emerging Growth Company false    
Entity Common Stock, Shares Outstanding   173,272,653  
Entity Public Float     $ 4.5