Goodwill and Intangible Assets - Goodwill Business Segments (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2019	Dec. 31, 2020	Dec. 31, 2018
Goodwill [Roll Forward]
Goodwill	$ 14,782	$ 14,653	$ 14,653	$ 14,544
Acquisitions	130	107
Reductions in goodwill related to divestitures		(1)
Goodwill, Other Increase (Decrease)	(1)	3
Credit Card
Goodwill [Roll Forward]
Goodwill	5,087	5,088	5,088	5,060
Acquisitions	0	25
Reductions in goodwill related to divestitures		0
Goodwill, Other Increase (Decrease)	(1)	3
Consumer Banking
Goodwill [Roll Forward]
Goodwill	4,645	4,645	4,645	4,600
Acquisitions	0	46
Reductions in goodwill related to divestitures		(1)
Goodwill, Other Increase (Decrease)	0	0
Commercial Banking
Goodwill [Roll Forward]
Goodwill	5,050	4,920	$ 4,920	$ 4,884
Acquisitions	130	36
Reductions in goodwill related to divestitures		0
Goodwill, Other Increase (Decrease)	$ 0	$ 0

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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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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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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