Crude Oil Supply and Inventory Purchase Agreement (Details) - USD ($) $ in Millions	1 Months Ended	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2019	Mar. 31, 2019	Sep. 30, 2019
Oil and Gas Delivery Commitments and Contracts [Line Items]
Gain on change in fair value resulting from modification of instruments			$ 7.6
Cash proceeds from change in contractual terms	$ 38.9
Gains on interest expense		$ 7.7		$ 11.4
Big Spring refinery | J. Aron
Oil and Gas Delivery Commitments and Contracts [Line Items]
Period of prior notice required to terminate Supply and Offtake Agreement				6 months