Inventories (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Inventory [Line Items]
Finished goods	$ 758	$ 1,027
Work in process	449	460
Raw materials	441	408
Materials and supplies	95	104
Inventories	1,743	$ 1,999
Motorparts
Inventory [Line Items]
Inventory write-down	$ 82

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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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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Amount before valuation and LIFO reserves of raw materials expected to be sold, or consumed within one year or operating cycle, if longer.

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Amount before valuation and LIFO reserves of merchandise or goods in the production process expected to be completed within one year or operating cycle, if longer.

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Amount before valuation and LIFO reserves of other inventory expected to be sold, or consumed within one year or operating cycle, if longer.

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