Loans and Leases - Net Loans (Details) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	$ 23,381	$ 25,789
Allowance for loan and lease losses	(70)	(67)
Loans and leases, net of allowance	23,311	25,722
Domestic
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans to investment funds	11,935	15,050
Senior secured bank loans	3,516	3,490
Loans to municipalities	966	902
Other	34	37
Commercial real estate	976	874
Total loans and leases	17,427	20,353
Non-U.S.
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans to investment funds	4,989	4,505
Senior secured bank loans	965	931
Total loans and leases	$ 5,954	$ 5,436

Loans Receivable, Gross, Commercial, Financial Institutions, Secured

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Loans and Leases Receivable, Gross, Commercial, Other

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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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