Amount of loss from the write-down 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.

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Name:	us-gaap_GoodwillImpairmentLoss
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Goodwill - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
Goodwill - Narrative (Details) - USD ($) $ in Millions	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Goodwill [Line Items]
Goodwill, Impairment Loss	$ 357	$ 1,614	$ 357	$ 1,614
Goodwill	1,407		1,407		$ 1,764
Operating segments \| Global Corporate & Investment Banking - U.S.
Goodwill [Line Items]
Goodwill, Impairment Loss			270
Goodwill	483		483		$ 667
Operating segments \| Commercial Banking and Real Estate Industries [Member]
Goodwill [Line Items]
Goodwill	$ 640		$ 640