Goodwill and Other Intangible Assets - Changes in the Carrying Amount of Goodwill by Reportable Segment (Detail) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Goodwill [Line Items]
Goodwill	$ 6,331	$ 6,331	$ 6,337
Goodwill, Purchase Accounting Adjustments		1
Goodwill, Written off Related to Sale of Business Unit		(7)
Goodwill, Transfers	0
Consumer [Member]
Goodwill [Line Items]
Goodwill	4,390	4,262	4,262
Goodwill, Purchase Accounting Adjustments		0
Goodwill, Written off Related to Sale of Business Unit		0
Goodwill, Transfers	128
Wholesale [Member]
Goodwill [Line Items]
Goodwill	1,941	2,069	$ 2,075
Goodwill, Purchase Accounting Adjustments		1
Goodwill, Written off Related to Sale of Business Unit		$ (7)
Goodwill, Transfers	$ (128)

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.

+ References

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Amount of transfers into (out 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.

+ References

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Amount of divestiture 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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