Contingencies, Commitments and Guarantees (Commitments and Guarantees - Narrative) (Details) - USD ($) $ in Billions	Sep. 30, 2015	Dec. 31, 2014
Commitments to Fund Partnership Investments, Bank Credit Facilities, Bridge Loans and Private Corporate Bond Investments
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Fair Value Disclosure, Off-balance Sheet Risks, Face Amount, Liability	$ 6.7	$ 5.3
Mortgage Loan Commitments
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Fair Value Disclosure, Off-balance Sheet Risks, Face Amount, Liability	$ 5.6	$ 4.0

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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