Inventories (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2017	Dec. 31, 2018
Inventory Disclosure [Abstract]
Effect of LIFO inventory liquidation on cost of goods sold		$ 66
Effect of LIFO Inventory Liquidation on Income		$ 49
Effect of LIFO inventory liquidation on profit per share		$ 0.08
Percentage of LIFO Inventory	60.00%		65.00%
Raw materials	$ 4,263		$ 4,477
Work-in-process	1,147		1,259
Finished goods	5,598		5,562
Supplies	258		231
Total inventories	11,266		$ 11,529
Long-term material purchase obligations	$ 270

Effect of LIFO inventory liquidation on cost of goods sold.

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Effect of LIFO inventory liquidation on profit per share.

+ References

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- Definition

The effect of liquidating LIFO (last in first out) inventory layers on income.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 330
-SubTopic 10
-Section S99
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Carrying amount, net of valuation reserves and adjustments, as of the balance sheet date of merchandise or goods held by the company that are readily available for sale.

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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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Carrying amount, net of valuation reserves and adjustments, as of the balance sheet date of unprocessed items to be consumed in the manufacturing or production process.

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Carrying amount, net of valuation reserves and adjustments, 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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Carrying amount, net of reserves and adjustments, as of the balance sheet date of merchandise or goods which are partially completed. This inventory is generally comprised of raw materials, labor and factory overhead costs, which require further materials, labor and overhead to be converted into finished goods, and which generally require the use of estimates to determine percentage complete and pricing.

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The minimum amount the entity agreed to spend under the long-term purchase commitment.

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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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