The charge against earnings resulting from the aggregate write down of all assets from their carrying value to their fair value.

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Fair Value Measurements, Nonrecurring (Details) (USD $) In Millions, unless otherwise specified					1 Months Ended		9 Months Ended					1 Months Ended	9 Months Ended	1 Months Ended	9 Months Ended	1 Months Ended	9 Months Ended					1 Months Ended	9 Months Ended
	Sep. 30, 2012	Dec. 31, 2011	Sep. 30, 2012 Fair Value, Measurements, Nonrecurring [Member]	Sep. 30, 2011 Fair Value, Measurements, Nonrecurring [Member]	Sep. 30, 2012 Aruba Refinery [Member]	Mar. 31, 2012 Aruba Refinery [Member]	Sep. 30, 2012 Aruba Refinery [Member]	Sep. 30, 2012 Aruba Refinery [Member] Fair Value, Measurements, Nonrecurring [Member]	Sep. 30, 2012 Aruba Refinery [Member] Fair Value, Measurements, Nonrecurring [Member] Fair Value, Inputs, Level 1 [Member]	Sep. 30, 2012 Aruba Refinery [Member] Fair Value, Measurements, Nonrecurring [Member] Fair Value, Inputs, Level 2 [Member]	Sep. 30, 2012 Aruba Refinery [Member] Fair Value, Measurements, Nonrecurring [Member] Fair Value, Inputs, Level 3 [Member]	Sep. 30, 2012 Refining Assets [Member]	Sep. 30, 2012 Refining Assets [Member]	Sep. 30, 2012 Inventory Related Assets [Member]	Sep. 30, 2012 Inventory Related Assets [Member]	Mar. 31, 2012 Construction in Progress [Member]	Sep. 30, 2012 Construction in Progress [Member]	Sep. 30, 2012 Construction in Progress [Member] Fair Value, Measurements, Nonrecurring [Member]	Sep. 30, 2012 Construction in Progress [Member] Fair Value, Measurements, Nonrecurring [Member] Fair Value, Inputs, Level 1 [Member]	Sep. 30, 2012 Construction in Progress [Member] Fair Value, Measurements, Nonrecurring [Member] Fair Value, Inputs, Level 2 [Member]	Sep. 30, 2012 Construction in Progress [Member] Fair Value, Measurements, Nonrecurring [Member] Fair Value, Inputs, Level 3 [Member]	Sep. 30, 2012 Retail [Member]	Sep. 30, 2012 Retail [Member]	Sep. 30, 2012 Retail [Member] Fair Value, Measurements, Nonrecurring [Member]	Sep. 30, 2012 Retail [Member] Fair Value, Measurements, Nonrecurring [Member] Fair Value, Inputs, Level 1 [Member]	Sep. 30, 2012 Retail [Member] Fair Value, Measurements, Nonrecurring [Member] Fair Value, Inputs, Level 2 [Member]	Sep. 30, 2012 Retail [Member] Fair Value, Measurements, Nonrecurring [Member] Fair Value, Inputs, Level 3 [Member]
Assets:
Long-lived assets, fair value						$ 350		$ 0	$ 0	$ 0	$ 0							$ 2	$ 0	$ 0	$ 2	$ 5	$ 5	$ 5	$ 0	$ 0	$ 5
Materials and supplies inventories	5,787	5,623						0	0	0	0
Asset impairment loss					333	595	928					308	903	25	25	16	16					12	12
Fair Value Measurements (Textual)
Long-lived assets, carrying value	25,873	25,177				945						308	308
Assets, nonrecurring				0
Liabilities, nonrecurring			$ 0	$ 0