Inventories (Schedule of Inventory) (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Inventory, Net [Abstract]
Finished products	$ 2,076	$ 2,374
Raw materials and work in process	617	725
Gross inventories	2,693	3,099
Less: excess of FIFO cost over LIFO cost	(160)	(111)
Total inventories	$ 2,533	$ 2,988
Percent of LIFO Inventory	41.00%	38.00%

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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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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The percentage of LIFO (last in first out) inventory to total inventory as of the balance sheet date if other than 100 percent.

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