Loans and Leases - Net Loans (Details) - USD ($) $ in Millions	Mar. 31, 2016	Dec. 31, 2015
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	$ 19,187	$ 18,799
Allowance for loan losses	(47)	(46)
Loans and leases, net of allowance for loan losses	19,140	18,753
Total Institutional
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	19,160	18,771
Commercial Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	27	28
U.S. \| Total Institutional
Accounts, Notes, Loans and Financing Receivable [Line Items]
Investment funds	11,681	11,136
Commercial and financial	3,707	4,671
Purchased receivables	86	93
Lease financing	335	337
U.S. \| Commercial Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial real estate	27	28
Non-U.S. \| Total Institutional
Accounts, Notes, Loans and Financing Receivable [Line Items]
Investment funds	2,247	1,678
Commercial and financial	541	278
Purchased receivables	0	0
Lease financing	$ 563	$ 578

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Purchased Receivables

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Amount before allowance of commercial leases and leveraged lease transactions where the entity is long-term creditor. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes leases covered under loss sharing agreements.

+ References

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-Name Accounting Standards Codification
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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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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.

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Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

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Amount before allowance of loans issued to financial institutions, including, but not limited to, real estate investment trusts, mortgage companies, and banks. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans covered under loss sharing agreements.

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Amount before allowance of commercial loans issued to businesses to acquire, develop, construct, improve, or refinance land or building. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans covered under loss sharing agreements.

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