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Asset Impairments - Identified Intangible Assets, by Major Classification (Detail) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Intangible Assets Net Excluding Goodwill [Line Items]
Gross	$ 1,472	$ 6,504
Accumulated Amortization	(620)	(3,484)
Net Book Value	852	3,020	$ 3,301
Indefinite-lived Trade Names [Member]
Intangible Assets Net Excluding Goodwill [Line Items]
Gross	280	383
Net Book Value	280	383
Customer Relationships [Member]
Intangible Assets Net Excluding Goodwill [Line Items]
Gross	598	4,078
Accumulated Amortization	(305)	(2,352)
Net Book Value	293	1,726
Trademarks [Member]
Intangible Assets Net Excluding Goodwill [Line Items]
Gross	190	891
Accumulated Amortization	(123)	(341)
Net Book Value	67	550
Patents [Member]
Intangible Assets Net Excluding Goodwill [Line Items]
Gross	121	661
Accumulated Amortization	(47)	(414)
Net Book Value	74	247
Other [Member]
Intangible Assets Net Excluding Goodwill [Line Items]
Gross	283	491
Accumulated Amortization	(145)	(377)
Net Book Value	$ 138	$ 114

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Intangible Assets Net Excluding Goodwill.

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Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Sum of the carrying amounts of all intangible assets, excluding goodwill, as of the balance sheet date, net of accumulated amortization and impairment charges.

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