v2.4.0.6

Inventories (Details) (USD $) In Millions, unless otherwise specified	Sep. 30, 2012	Dec. 31, 2011
Inventories
Crude oil and petroleum products	$ 436	$ 3,633
Materials, supplies and other	740	998
Total Inventories	1,176	4,631	[1]
Inventories (Textual) [Abstract]
Inventories valued on the LIFO basis	332	3,387
Excess of current replacement cost over LIFO cost of inventories	$ 100	$ 8,400
[1] **Certain amounts have been restated to reflect a prior period adjustment. See Note 16—Accumulated Other Comprehensive Income, in the Notes to Consolidated Financial Statements.

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The excess of replacement or current cost over the stated LIFO (last in first out) inventory value when the LIFO inventory method is utilized.

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Carrying amount as of the balance sheet date of finished goods inventories for petroleum products, crude oil, petrochemical products, and other oil and gas inventories.

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Carrying amount (lower of cost or market) as of the balance sheet date of inventories less all valuation and other allowances. Excludes noncurrent inventory balances (expected to remain on hand past one year or one operating cycle, if longer).

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The amount of LIFO (last in first out) inventory present at the reporting date when inventory is also valued using different valuation methods.

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Gross amount of products used directly or indirectly in the manufacturing or production process, which may or may not become part of the final product. May also include items used in the storage, presentation or transportation of physical goods.

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