[Line Items] for For a long-lived asset, the table may include a description of the impaired long-lived asset and facts and circumstances leading to the impairment, amount of the impairment loss and where the loss is located in the income statement, method(s) for determining fair value, and the segment in which the impaired long-lived asset is reported.

No definition available.

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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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The aggregate amount of write-downs for impairments recognized during the period for long lived assets held for use (including those held for disposal by means other than sale).

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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The aggregate amount of write-downs for impairments recognized during the period for long-lived assets held for abandonment, exchange or sale.

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Impairments (Narrative) (Details) - USD ($) $ in Millions	1 Months Ended	12 Months Ended
Impairments (Narrative) (Details) - USD ($) $ in Millions	Jul. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Schedule of Impaired Long-Lived Assets [Line Items]
Held-for-use impairment			$ 131
Before-tax loss on net PP&E held for sale			12
Impairments		$ 7	150	$ 29
Refining [Member]
Schedule of Impaired Long-Lived Assets [Line Items]
Impairments		3	147	3
Refining [Member] \| Bantry Bay Terminal [Member]
Schedule of Impaired Long-Lived Assets [Line Items]
Before-tax loss on net PP&E held for sale			12
Refining [Member] \| IRELAND \| Bantry Bay Terminal [Member]
Schedule of Impaired Long-Lived Assets [Line Items]
Before-tax loss on net PP&E held for sale	$ 12
Refining [Member] \| Whitegate Refinery [Member] \| IRELAND
Schedule of Impaired Long-Lived Assets [Line Items]
Held-for-use impairment			131
Marketing And Specialties [Member]
Schedule of Impaired Long-Lived Assets [Line Items]
Impairments		$ 3	$ 3	$ 16