Loans and Leases - Net Loans (Details) - USD ($) $ in Millions	Dec. 31, 2016	Dec. 31, 2015
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	$ 19,757	$ 18,799
Allowance for loan and lease losses	(53)	(46)
Loans and leases, net of allowance	19,704	18,753
Domestic
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans to investment funds	11,734	11,915
Senior secured bank loans	3,256	2,929
Loans to municipalities	1,352	962
Other	70	93
Commercial real estate	27	28
Lease financing	338	337
Total loans and leases	16,777	16,264
Foreign
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans to investment funds	2,224	1,752
Senior secured bank loans	252	205
Lease financing	504	578
Total loans and leases	$ 2,980	$ 2,535

Loans Receivable, Gross, Commercial, Financial Institutions, Secured

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Loans and Leases Receivable, Gross, Commercial, Other

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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.

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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 issued to a unit or agency of a federal, state or local jurisdiction within the country of domicile of the reporting entity. 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 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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