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, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Earnings Per Share [Abstract]
Net income attributable to HollyFrontier stockholders	$ (176,677)	$ 196,915	$ (481,300)	$ 449,970
Participating securities’ (restricted stock) share in earnings	0	283	0	647
Net income (loss) attributable to common shares	$ (176,677)	$ 196,632	$ (481,300)	$ 449,323
Average number of shares of common stock outstanding	161,889	169,356	161,882	170,100
Effect of dilutive variable restricted shares and performance share units	0	1,191	0	1,164
Average number of shares of common stock outstanding assuming dilution	161,889	170,547	161,882	171,264
Basic earnings (loss) per share	$ (1.09)	$ 1.16	$ (2.97)	$ 2.64
Diluted earnings (loss) per share	$ (1.09)	$ 1.15	$ (2.97)	$ 2.62
Excludes anti-dilutive restricted and performance share units of:	590	160	585	131