Loans and Leases - Schedule of Allowance for Loan Losses (Details) - USD ($) $ in Millions	Sep. 30, 2015	Dec. 31, 2014
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Evaluated for Impairment	$ 19,067	$ 18,199
Institutional
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Evaluated for Impairment	19,016	18,171
Amount of loan losses related to institutional loans collectively evaluated for impairment	48	38
Commercial Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Evaluated for Impairment	51	28
Collectively Evaluated for Impairment
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Evaluated for Impairment	19,067	18,199
Collectively Evaluated for Impairment \| Institutional
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Evaluated for Impairment	19,016	18,171
Collectively Evaluated for Impairment \| Commercial Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and Leases Evaluated for Impairment	$ 51	$ 28

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- Definition

The balance of financing receivables that were collectively evaluated for impairment.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 11B

-Subparagraph (h)

-URI http://asc.fasb.org/extlink&oid=35738203&loc=SL6953423-111524

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- Definition

Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=28367877&loc=d3e4428-111522

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