Description of Business - Narrative (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2020	Mar. 31, 2020	Jun. 30, 2019	Mar. 31, 2019	Jun. 30, 2020
Asset impairment charges	$ 29				$ 500
Restructuring charges	96	$ 15	$ 49	$ 16
Severance
Restructuring charges	90	$ 10	$ 44	$ 11
Motorparts
Inventory write-down	82				82
Asset impairment charges	16				16
Operating lease impairment	9				9
Motorparts \| Severance
Restructuring charges	$ 4				$ 4

Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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Amount of loss from reductions in inventory due to subsequent measurement adjustments, including, but not limited to, physical deterioration, obsolescence, or changes in price levels.

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Amount of loss from impairment of right-of-use asset from operating lease.

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Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

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