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Description of Business - Narrative (Details) - USD ($) $ in Millions	3 Months Ended						9 Months Ended
	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Sep. 30, 2020
Restructuring Cost and Reserve [Line Items]
Asset impairment charges	$ 3						$ 503
Restructuring charges	19	$ 96	$ 15	$ 27	$ 49	$ 16
Severance
Restructuring Cost and Reserve [Line Items]
Restructuring charges	$ 16	$ 90	$ 10	$ 22	$ 44	$ 11
Motorparts
Restructuring Cost and Reserve [Line Items]
Inventory write-down							82
Asset impairment charges							16
Operating lease impairment							9
Motorparts \| Severance
Restructuring Cost and Reserve [Line Items]
Restructuring charges							$ 4