Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Fair value of financial and nonfinancial obligations.

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Fair value portion of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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Fair Value Measurements, Nonrecurring (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended			1 Months Ended		6 Months Ended	1 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012	Dec. 31, 2012	Sep. 30, 2012 Aruba Refinery [Member]	Mar. 31, 2012 Aruba Refinery [Member]	Jun. 30, 2012 Aruba Refinery [Member]	Sep. 30, 2012 Refining Assets [Member]	Mar. 31, 2012 Construction in Progress [Member]	Jun. 30, 2012 Construction in Progress [Member]	Jun. 30, 2013 Fair Value, Measurements, Nonrecurring [Member]	Dec. 31, 2012 Fair Value, Measurements, Nonrecurring [Member]	Dec. 31, 2012 Fair Value, Measurements, Nonrecurring [Member] Construction in Progress [Member]	Dec. 31, 2012 Fair Value, Measurements, Nonrecurring [Member] Retail [Member]	Dec. 31, 2012 Fair Value, Measurements, Nonrecurring [Member] Fair Value, Inputs, Level 1 [Member] Construction in Progress [Member]	Dec. 31, 2012 Fair Value, Measurements, Nonrecurring [Member] Fair Value, Inputs, Level 1 [Member] Retail [Member]	Dec. 31, 2012 Fair Value, Measurements, Nonrecurring [Member] Fair Value, Inputs, Level 2 [Member] Construction in Progress [Member]	Dec. 31, 2012 Fair Value, Measurements, Nonrecurring [Member] Fair Value, Inputs, Level 2 [Member] Retail [Member]	Mar. 31, 2012 Fair Value, Measurements, Nonrecurring [Member] Fair Value, Inputs, Level 3 [Member] Aruba Refinery [Member]	Dec. 31, 2012 Fair Value, Measurements, Nonrecurring [Member] Fair Value, Inputs, Level 3 [Member] Construction in Progress [Member]	Dec. 31, 2012 Fair Value, Measurements, Nonrecurring [Member] Fair Value, Inputs, Level 3 [Member] Retail [Member]
Assets:
Long-lived assets, fair value														$ 2	$ 8	$ 0	$ 0	$ 0	$ 0	$ 350	$ 2	$ 8
Fair Value Measurements (Textual)
Assets measured at fair value, nonrecurring												0
Liabilities measured at fair value, nonrecurring												0	0
Asset impairment losses	0	0	0	611		333	595	595	308	16	16
Long-lived assets, carrying value	$ 25,386		$ 25,386		$ 26,300		$ 945