Commitments, Guarantees, And Contingencies (Narrative) (Details) $ in Millions	Mar. 31, 2017 USD ($)
Loss Contingencies [Line Items]
Outstanding committed capital to certain entities	$ 13.9
Business Development Corporations [Member]
Loss Contingencies [Line Items]
Outstanding committed capital to certain entities	$ 10.2

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.

No definition available.

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