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Goodwill and Intangible Assets - Goodwill Business Segments (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2020	Dec. 31, 2017
Goodwill [Line Items]
Goodwill	$ 14,653	$ 14,544	$ 14,653	$ 14,533
Acquisitions	107	33
Reductions in goodwill related to divestitures	(1)	(17)
Other adjustments	3	(5)
Credit Card
Goodwill [Line Items]
Goodwill	5,088	5,060	5,088	5,032
Acquisitions	25	33
Reductions in goodwill related to divestitures	0	0
Other adjustments	3	(5)
Consumer Banking
Goodwill [Line Items]
Goodwill	4,645	4,600	4,645	4,600
Acquisitions	46	0
Reductions in goodwill related to divestitures	(1)	0
Other adjustments	0	0
Commercial Banking
Goodwill [Line Items]
Goodwill	4,920	4,884	$ 4,920	$ 4,901
Acquisitions	36	0
Reductions in goodwill related to divestitures	0	(17)
Other adjustments	$ 0	$ 0

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://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(10)(1))
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+ References

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