Non-Interest Revenue and Expense Detail (Details 2) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Details Of Certain Statements Of Income Lines Details [Abstract]
Professional services	$ 2,070	$ 2,583	$ 2,750
Occupancy and equipment	2,019	1,838	1,854
Communications	276	302	345
Gain on sale of HFS Portfolios		(1,218)
Other	1,411	1,657	1,844
Total Other, net	$ 5,776	$ 5,162	$ 6,793

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.

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No definition available.

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- Definition

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

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.4)
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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.

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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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- Definition

A fee charged for services from professionals such as doctors, lawyers and accountants. The term is often expanded to include other professions, for example, pharmacists charging to maintain a medicinal profile of a client or customer.

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