Document And Entity Information - shares	9 Months Ended
	Sep. 30, 2020	Oct. 30, 2020
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Sep. 30, 2020
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		162,017,259
Entity Central Index Key	0000048039
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	Q3
Amendment Flag	false