Earnings Per Share (Schedule Of Earnings Per Share) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Earnings Per Share [Abstract]
Net income attributable to HollyFrontier stockholders	$ 196,915	$ 345,507	$ 449,970	$ 613,598
Participating securities’ (restricted stock) share in earnings	283	1,196	647	2,147
Net income (loss) attributable to common shares	$ 196,632	$ 344,311	$ 449,323	$ 611,451
Average number of shares of common stock outstanding	169,356	175,899	170,100	176,256
Effect of dilutive variable restricted shares and performance share units	1,191	1,687	1,164	1,564
Average number of shares of common stock outstanding assuming dilution	170,547	177,586	171,264	177,820
Basic earnings (loss) per share	$ 1.16	$ 1.96	$ 2.64	$ 3.47
Diluted earnings (loss) per share	$ 1.15	$ 1.94	$ 2.62	$ 3.44
Excludes anti-dilutive restricted and performance share units of:	160	648	131	753