Inventories (Details) (USD $) In Millions	Sep. 30, 2011	Dec. 31, 2010
Inventories
Finished goods	$ 1,640	$ 1,484
Raw materials and work in process	5,800	5,449
Supplies	293	315
Total (approximates current cost)	7,733	7,248
Reduction to LIFO costs	(112)	(186)
Inventories	7,621	7,062
Recognized as:
Inventories	6,239	5,868
Other assets	$ 1,382	$ 1,194

Inventories included in other assets.

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Total of current and noncurrent inventories.

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Recognized as [Abstract].

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Carrying amount as of the balance sheet date of merchandise or goods held by the company that are readily available for sale.

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Gross amount, as of the balance sheet date, of merchandise, goods, commodities, or supplies held for future sale or to be used in manufacturing, servicing or production process.

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Reflects the difference between (a) inventory at the lower of LIFO cost or market and (b) inventory at replacement cost or at the lower of some acceptable inventory accounting method (such as FIFO or average cost), or market. If material, reflects an excess of replacement or current cost over stated LIFO value parenthetically on the balance sheet or in a note to the financial statements.

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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 aggregate carrying amount as of the balance sheet date of items held by the entity which are partially completed at the time of measurement and unprocessed items that will go through the production process and become part of the final product. Includes supplies used directly or indirectly in the manufacturing or production process. This element may be used when the reporting entity combines work in process and raw materials into an aggregate amount.

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Carrying amount as of the balance sheet date 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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