Non-Interest Revenue and Expense Detail (Details 2) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016
Details Of Certain Statements Of Income Lines Details [Abstract]
Professional services	$ 512	$ 604
Occupancy and equipment	475	465
Communications	63	83
Gain on sale of held for sale (HFS) portfolio	0	(127)
Other	357	395
Total other, net	$ 1,407	$ 1,420

Details of Certain Statements of Income Lines Details.

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- Definition

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

The amount of expense in the period for communications and data processing expense.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.4)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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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
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-Topic 942
-SubTopic 225
-Section S99
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-Subparagraph (SX 210.9-04.14(b))
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-Name Accounting Standards Codification
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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.

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