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Goodwill and Intangible Assets - Goodwill Attributable to Each Business Segments (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Goodwill [Roll Forward]
Goodwill, beginning balance	$ 14,544	$ 14,533	$ 14,519
Acquisitions	107	33	6
Reductions in goodwill related to divestitures	(1)	(17)
Other adjustments	3	(5)	8
Goodwill, ending balance	14,653	14,544	14,533
Credit Card
Goodwill [Roll Forward]
Goodwill, beginning balance	5,060	5,032	5,018
Acquisitions	25	33	6
Reductions in goodwill related to divestitures	0	0
Other adjustments	3	(5)	8
Goodwill, ending balance	5,088	5,060	5,032
Consumer Banking
Goodwill [Roll Forward]
Goodwill, beginning balance	4,600	4,600	4,600
Acquisitions	46	0	0
Reductions in goodwill related to divestitures	(1)	0
Other adjustments	0	0	0
Goodwill, ending balance	4,645	4,600	4,600
Commercial Banking
Goodwill [Roll Forward]
Goodwill, beginning balance	4,884	4,901	4,901
Acquisitions	36	0	0
Reductions in goodwill related to divestitures	0	(17)
Other adjustments	0	0	0
Goodwill, ending balance	$ 4,920	$ 4,884	$ 4,901

X

- Definition

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
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- Definition

Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

+ References

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- Definition

Amount of increase (decrease), classified as other, of an asset representing the future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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- Definition

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.

+ References

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