Inventory (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Inventory
Finished goods	$ 190	$ 220
Work in process and raw materials	1,649	1,399
Total	$ 1,839	$ 1,619

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- Definition

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.

+ References

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- Definition

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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- Definition

The aggregate carrying amount, net of valuation reserves and adjustments, as of the balance sheet date of items 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. This element may be used when the reporting entity combines work in process and raw materials into an aggregate amount.

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