Inventories (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2015
Schedule of Inventories
Refinery feedstocks	$ 2,244		$ 2,244		$ 2,404
Refined products and blendstocks	3,283		3,283		3,774
Ethanol feedstocks and products	202		202		242
Materials and supplies	250		250		244
Inventories, before lower of cost or market inventory valuation reserve	5,979		5,979		6,664
Lower of cost or market inventory valuation reserve	0		0		(766)
Inventories	5,979		5,979		5,898
Inventories (Textual)
Lower of cost or market inventory valuation adjustment	0	$ 0	747	$ 0
Excess of market value over carrying amount of LIFO inventories	1,200		1,200
Amount of non-LIFO inventory	$ 675		$ 675		$ 668