Inventories - Inventories (Details) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Inventory Disclosure [Abstract]
Finished goods	$ 1,698	$ 1,658
Raw materials and work in process	5,217	5,004
Supplies	201	194
Total (approximates current cost)	7,116	6,856
(Decrease) increase to LIFO costs	(6)	1
Total current and noncurrent inventories	7,110	6,857
Recognized as:
Inventories	5,712	5,440
Other assets	$ 1,398	$ 1,417

Total of current and noncurrent inventories.

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Recognized as.

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Amount before valuation and LIFO reserves of completed merchandise or goods expected to be sold within one year or operating cycle, if longer.

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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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Amount by which inventory stated at last-in first-out (LIFO) is less than (in excess of) inventory stated at other inventory cost methods.

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Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

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Inventories not expected to be converted to cash, sold or exchanged within the normal operating cycle.

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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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Amount before valuation and LIFO reserves of other supplies used within the manufacturing or production process expected to be consumed within one year or operating cycle, if longer.

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