Inventories - Schedule of Inventories (Details) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Inventory Disclosure [Abstract]
Finished goods	$ 1,628	$ 1,610
Raw materials and work in process	6,135	5,949
Supplies	190	146
Total (approximates current cost)	7,953	7,705
Increase (decrease) to LIFO cost	23	(81)
Total current and noncurrent inventories	7,976	7,624
Recognized as:
Inventories	5,603	5,554
Other assets	$ 2,373	$ 2,070

Total of current and noncurrent inventories.

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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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