Inventories (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015	Dec. 31, 2015
Schedule of Inventories
Refinery feedstocks	$ 2,389		$ 2,389		$ 2,404
Refined products and blendstocks	3,271		3,271		3,774
Ethanol feedstocks and products	226		226		242
Materials and supplies	251		251		244
Inventories, before lower of cost or market inventory valuation reserve	6,137		6,137		6,664
Lower of cost or market inventory valuation reserve	0		0		(766)
Inventories	6,137		6,137		5,898
Inventories (Textual)
Lower of cost or market inventory valuation adjustment	(454)	$ 0	(747)	$ 0
Excess of market value over carrying amount of LIFO inventories	713		713
Amount of non-LIFO inventory	$ 681		$ 681		$ 668