Document And Entity Information - shares
6 Months Ended
Jun. 30, 2019
Jul. 26, 2019
Cover page.    
Document Type 10-Q  
Document Quarterly Report true  
Document Period End Date Jun. 30, 2019  
Document Transition Report false  
Entity File Number 1-3876  
Entity Registrant Name HOLLYFRONTIER CORP  
Entity Incorporation, State or Country Code DE  
Entity Tax Identification Number 75-1056913  
Entity Address, Address Line One 2828 N. Harwood, Suite 1300  
Entity Address, City or Town Dallas  
Entity Address, State or Province TX  
Entity Address, Postal Zip Code 75201  
City Area Code 214  
Local Phone Number 871-3555  
Title of 12(b) Security Common Stock $0.01 par value  
Trading Symbol HFC  
Security Exchange Name NYSE  
Entity Current Reporting Status Yes  
Entity Interactive Data Current Yes  
Entity Filer Category Large Accelerated Filer  
Entity Small Business false  
Entity Emerging Growth Company false  
Entity Shell Company false  
Entity Common Stock, Shares Outstanding   164,578,167
Entity Central Index Key 0000048039  
Current Fiscal Year End Date --12-31  
Document Fiscal Year Focus 2019  
Document Fiscal Period Focus Q2  
Amendment Flag false