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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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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No definition available.

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

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The balance of financing receivables that were individually 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.

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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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Bank Loans (Recorded Balances Of Loans and Amount Of Allowance Allocated Based Upon Impairment Method by Portfolio Segment) (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Jun. 30, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Dec. 31, 2014
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for Loan Losses, Individually Evaluated for Impairment	$ 2,595		$ 187	$ 194
Allowance for Loan Losses, Collectively Evaluated for Impairment	36,550		29,600	27,513
Allowance for Loan Losses, Total	39,145	$ 35,866	29,787	27,707	$ 23,923	$ 20,731
Recorded Investment in Loans, Individually Evaluated for Impairment	28,301		519	1,289
Recorded Investment in Loans, Collectively Evaluated for Impairment	4,968,743		3,180,065	2,441,054
Recorded Investment in Loans, Total	4,997,044		3,180,584	2,442,343
Commercial And Industrial [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for Loan Losses, Individually Evaluated for Impairment	2,415
Allowance for Loan Losses, Collectively Evaluated for Impairment	29,765		24,748	22,414
Allowance for Loan Losses, Total	32,180	29,816	24,748	22,414	19,297	16,609
Recorded Investment in Loans, Individually Evaluated for Impairment	17,938
Recorded Investment in Loans, Collectively Evaluated for Impairment	1,540,346		1,216,656	1,121,643
Recorded Investment in Loans, Total	1,558,284		1,216,656	1,121,643
Securities Based Loans [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for Loan Losses, Collectively Evaluated for Impairment	1,903		1,607	1,506
Allowance for Loan Losses, Total	1,903	1,731	1,607	1,506	1,445	1,099
Recorded Investment in Loans, Collectively Evaluated for Impairment	1,452,913		1,388,953	1,004,142
Recorded Investment in Loans, Total	1,452,913		1,388,953	1,004,142
Consumer [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for Loan Losses, Individually Evaluated for Impairment	7		14	21
Allowance for Loan Losses, Collectively Evaluated for Impairment	288		91	86
Allowance for Loan Losses, Total	295	107	105	107	123	156
Recorded Investment in Loans, Individually Evaluated for Impairment	9		14	21
Recorded Investment in Loans, Collectively Evaluated for Impairment	92,565		36,832	22,034
Recorded Investment in Loans, Total	92,574		36,846	22,055
Residential Real Estate [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for Loan Losses, Individually Evaluated for Impairment	24		24	24
Allowance for Loan Losses, Collectively Evaluated for Impairment	1,851		1,217	1,098
Allowance for Loan Losses, Total	1,875	1,529	1,241	1,122	904	787
Recorded Investment in Loans, Individually Evaluated for Impairment	509		182	945
Recorded Investment in Loans, Collectively Evaluated for Impairment	1,803,603		428,950	260,013
Recorded Investment in Loans, Total	1,804,112		429,132	260,958
Commercial Real Estate [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for Loan Losses, Collectively Evaluated for Impairment	504		264	264
Allowance for Loan Losses, Total	504	512	264	264	286	232
Recorded Investment in Loans, Individually Evaluated for Impairment	9,522
Recorded Investment in Loans, Collectively Evaluated for Impairment	54,158		92,623	19,811
Recorded Investment in Loans, Total	63,680		92,623	19,811
Home Equity Lines Of Credit [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for Loan Losses, Individually Evaluated for Impairment	149		149	149
Allowance for Loan Losses, Collectively Evaluated for Impairment	136		141	104
Allowance for Loan Losses, Total	285	283	290	253	265	267
Recorded Investment in Loans, Individually Evaluated for Impairment	323		323	323
Recorded Investment in Loans, Collectively Evaluated for Impairment	14,091		12,152	10,937
Recorded Investment in Loans, Total	14,414		12,475	11,260
Construction And Land [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for Loan Losses, Collectively Evaluated for Impairment	203		78	47
Allowance for Loan Losses, Total	203	144	78	47
Recorded Investment in Loans, Collectively Evaluated for Impairment	11,067		3,899	2,474
Recorded Investment in Loans, Total	11,067		3,899	2,474
Qualitative [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for Loan Losses, Collectively Evaluated for Impairment	1,900		1,454	1,994
Allowance for Loan Losses, Total	$ 1,900	$ 1,744	$ 1,454	$ 1,994	$ 1,603	$ 1,581