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Basis of Presentation Basis of Presentation - Narrative (Details) | 3 Months Ended
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Mar. 31, 2017 segment revenue_line
Segment Reporting, Revenue Reconciling Item [Line Items] |
Number of reportable segments | segment | 1
Number of revenue lines | 5
Commissions, Fees and Other and Fiduciary Investment Income |
Segment Reporting, Revenue Reconciling Item [Line Items] |
Number of revenue lines | 1

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- Definition Number of Revenue Lines + References No definition available. + Details
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X
- Definition Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements. + References No definition available. + Details
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Period Type: | duration

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- Definition 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. + References No definition available. + Details
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Namespace Prefix: | us-gaap_
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Period Type: | duration

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- Details
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Namespace Prefix: |
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Balance Type: |
Period Type: |