Goodwill and Other Identifiable Intangible Assets (Carrying Amount of Goodwill) (Details) $ in Millions	3 Months Ended
Mar. 31, 2019 USD ($)
Goodwill [Roll Forward]
Beginning Balance	$ 4,070
Acquisitions	48
Currency	(15)
Ending Balance	4,103
Performance Coatings [Member]
Goodwill [Roll Forward]
Beginning Balance	3,266
Acquisitions	2
Currency	(11)
Ending Balance	3,257
Industrial Coatings [Member]
Goodwill [Roll Forward]
Beginning Balance	804
Acquisitions	46
Currency	(4)
Ending Balance	$ 846

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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-Publisher FASB
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Amount of increase (decrease) from adjustments after acquisition date under purchase accounting 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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Amount of increase (decrease) from foreign currency translation adjustments and purchase accounting adjustments 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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