Bank Loans (Recorded Balances Of Loans and Amount Of Allowance Allocated Based Upon Impairment Method by Portfolio Segment) (Details) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015	Mar. 31, 2015	Dec. 31, 2014
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for Loan Losses, Individually Evaluated for Impairment	$ 2,383	$ 187
Allowance for Loan Losses, Collectively Evaluated for Impairment	31,667	29,600
Allowance for Loan Losses, Total	34,050	29,787	$ 22,568	$ 20,731
Recorded Investment in Loans, Individually Evaluated for Impairment	23,002	519
Recorded Investment in Loans, Collectively Evaluated for Impairment	3,482,507	3,180,065
Recorded Investment in Loans, Total	3,505,509	3,180,584
Commercial And Industrial [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for Loan Losses, Individually Evaluated for Impairment	1,215
Allowance for Loan Losses, Collectively Evaluated for Impairment	26,485	24,748
Allowance for Loan Losses, Total	27,700	24,748	18,104	16,609
Recorded Investment in Loans, Individually Evaluated for Impairment	12,148
Recorded Investment in Loans, Collectively Evaluated for Impairment	1,283,170	1,216,656
Recorded Investment in Loans, Total	1,295,318	1,216,656
Securities Based Loans [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for Loan Losses, Collectively Evaluated for Impairment	1,605	1,607
Allowance for Loan Losses, Total	1,605	1,607	1,288	1,099
Recorded Investment in Loans, Collectively Evaluated for Impairment	1,345,719	1,388,953
Recorded Investment in Loans, Total	1,345,719	1,388,953
Consumer [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for Loan Losses, Individually Evaluated for Impairment	14	14
Allowance for Loan Losses, Collectively Evaluated for Impairment	70	91
Allowance for Loan Losses, Total	84	105	105	156
Recorded Investment in Loans, Individually Evaluated for Impairment	18	14
Recorded Investment in Loans, Collectively Evaluated for Impairment	31,018	36,832
Recorded Investment in Loans, Total	31,036	36,846
Residential Real Estate [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for Loan Losses, Individually Evaluated for Impairment	24	24
Allowance for Loan Losses, Collectively Evaluated for Impairment	1,306	1,217
Allowance for Loan Losses, Total	1,330	1,241	857	787
Recorded Investment in Loans, Individually Evaluated for Impairment	704	182
Recorded Investment in Loans, Collectively Evaluated for Impairment	729,979	428,950
Recorded Investment in Loans, Total	730,683	429,132
Commercial Real Estate [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for Loan Losses, Individually Evaluated for Impairment	981
Allowance for Loan Losses, Collectively Evaluated for Impairment	308	264
Allowance for Loan Losses, Total	1,289	264	305	232
Recorded Investment in Loans, Individually Evaluated for Impairment	9,809
Recorded Investment in Loans, Collectively Evaluated for Impairment	73,464	92,623
Recorded Investment in Loans, Total	83,273	92,623
Home Equity Lines Of Credit [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for Loan Losses, Individually Evaluated for Impairment	149	149
Allowance for Loan Losses, Collectively Evaluated for Impairment	118	141
Allowance for Loan Losses, Total	267	290	269	267
Recorded Investment in Loans, Individually Evaluated for Impairment	323	323
Recorded Investment in Loans, Collectively Evaluated for Impairment	12,188	12,152
Recorded Investment in Loans, Total	12,511	12,475
Construction And Land [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for Loan Losses, Collectively Evaluated for Impairment	118	78
Allowance for Loan Losses, Total	118	78
Recorded Investment in Loans, Collectively Evaluated for Impairment	6,969	3,899
Recorded Investment in Loans, Total	6,969	3,899
Qualitative [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for Loan Losses, Collectively Evaluated for Impairment	1,657	1,454
Allowance for Loan Losses, Total	$ 1,657	$ 1,454	$ 1,640	$ 1,581

The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

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Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

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The balance of financing receivables that were collectively evaluated for impairment.

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (g)
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-Publisher FASB
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.7(d))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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-Publisher FASB
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-Publisher SEC
-Name Staff Accounting Bulletin (SAB)
-Number Topic 6
-Section L
-Subsection 1

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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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