Non-Interest Revenue and Expense Detail (Details 2) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Details Of Certain Statements Of Income Lines Details [Abstract]
Professional services	$ 521	$ 628	$ 1,033	$ 1,232
Occupancy and equipment	484	438	959	903
Gain on sale of held for sale (HFS) portfolio	0	(1,091)	0	(1,218)
Other	371	495	791	973
Total other, net	$ 1,376	$ 470	$ 2,783	$ 1,890

Details of Certain Statements of Income Lines Details.

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Represents other, net expenses from miscellaneous items within other revenues not previously classified.

+ References

No definition available.

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- Definition

The aggregate amount of professional services fees and other processing expenses.

+ References

No definition available.

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- Definition

Amount of net occupancy expense that may include items, such as depreciation of facilities and equipment, lease expenses, property taxes and property and casualty insurance expense.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.14(b))
-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

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-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
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-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 30
-Section 50
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Amount of noninterest expense classified as other.

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- Definition

The cash inflow resulting from the sale of loans classified as held-for-sale, including proceeds from loans sold through mortgage securitization.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 16
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3337-108585

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