Goodwill and Other Intangible Assets - Schedule of Goodwill (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014
Goodwill rollforward
Goodwill, beginning of year	$ 3,225	$ 3,228
Net change from business combinations	0	(3)
Goodwill, end of year	3,225	3,225
Regional Bank [Member] [Domain]
Goodwill rollforward
Goodwill, beginning of year	2,126
Goodwill, end of year	2,126	2,126
Commercial Banking
Goodwill rollforward
Goodwill, beginning of year	407
Goodwill, end of year	407	407
Transaction Banking
Goodwill rollforward
Goodwill, beginning of year	251
Goodwill, end of year	251	251
Investment Banking and Markets
Goodwill rollforward
Goodwill, beginning of year	427
Goodwill, end of year	427	427
Asian Corporate Banking
Goodwill rollforward
Goodwill, beginning of year	14
Goodwill, end of year	$ 14	$ 14

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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

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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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

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- Definition

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

+ References

No definition available.

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