Inventories - Schedule of inventories (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Schedule of Inventory [Line Items]
Raw materials	$ 1,888	$ 1,880
Work in process	235	352
Finished goods	507	670
Inventories	814	801
Inventory, Noncurrent	1,816	2,101
Assets, Total
Schedule of Inventory [Line Items]
Inventories	$ 2,630	$ 2,902

[Line Items] for Disclosure of information about inventory.

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

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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 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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