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, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Earnings Per Share [Abstract]
Net income (loss) attributable to HollyFrontier stockholders	$ 57,767	$ (409,368)	$ 12,299	$ (388,115)
Participating securities’ share in earnings	373	216	752	432
Net income(loss) attributable to common shares	$ 57,394	$ (409,584)	$ 11,547	$ (388,547)
Average number of shares of common stock outstanding	176,147	175,865	176,141	176,301
Effect of dilutive variable restricted shares and performance share units	155	0	349	0
Average number of shares of common stock outstanding assuming dilution	176,302	175,865	176,490	176,301
Basic earnings (loss) per share	$ 0.33	$ (2.33)	$ 0.07	$ (2.20)
Diluted earnings (loss) per share	$ 0.33	$ (2.33)	$ 0.07	$ (2.20)
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	140	191	133	183