Goodwill And Other Intangible Assets - Summary of Changes in Goodwill of Operating and Reporting Segment (Details) - USD ($) $ in Millions	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019
Goodwill [Line Items]
Beginning Balance	$ 2,041	$ 1,941
Acquisitions		78
Measurement period adjustment	25
Net current period impact to goodwill	21	78
Ending Balance	2,062	$ 2,019
Walker Die Casting
Goodwill [Line Items]
Walker Die Casting net working capital settlement	$ (4)

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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