Goodwill (Details) $ in Millions	9 Months Ended
Sep. 30, 2019 USD ($)
Changes in goodwill
Beginning Balance	$ 2,521
Foreign currency translation adjustments	11
Ending Balance	2,532
Goodwill impairment	0
Operating Segments \| Transportation
Changes in goodwill
Beginning Balance	1,040
Foreign currency translation adjustments	7
Ending Balance	1,047
Operating Segments \| Facilities
Changes in goodwill
Beginning Balance	978
Foreign currency translation adjustments	2
Ending Balance	980
Operating Segments \| Supply and Logistics
Changes in goodwill
Beginning Balance	503
Foreign currency translation adjustments	2
Ending Balance	$ 505

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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