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, 2017	Jun. 30, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Dec. 31, 2015
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for Loan Losses, Individually Evaluated for Impairment	$ 2,307		$ 3,375
Allowance for Loan Losses, Collectively Evaluated for Impairment	59,922		41,788
Allowance for Loan Losses, Total	62,229	$ 54,202	45,163	$ 39,145	$ 35,866	$ 29,787
Recorded Investment in Loans, Individually Evaluated for Impairment	15,009		26,934
Recorded Investment in Loans, Collectively Evaluated for Impairment	6,868,882		5,610,631
Recorded Investment in Loans, Total	6,883,891		5,637,565
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	7,111		2,636
Allowance for Loan Losses, Total	7,135	5,569	2,660	1,875	1,529	1,241
Recorded Investment in Loans, Individually Evaluated for Impairment	173		178
Recorded Investment in Loans, Collectively Evaluated for Impairment	2,517,370		2,161,222
Recorded Investment in Loans, Total	2,517,543		2,161,400
Commercial And Industrial [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for Loan Losses, Individually Evaluated for Impairment	2,131		2,392
Allowance for Loan Losses, Collectively Evaluated for Impairment	45,021		32,735
Allowance for Loan Losses, Total	47,152	40,805	35,127	32,180	29,816	24,748
Recorded Investment in Loans, Individually Evaluated for Impairment	14,511		16,815
Recorded Investment in Loans, Collectively Evaluated for Impairment	2,365,906		1,693,584
Recorded Investment in Loans, Total	2,380,417		1,710,399
Securities-Based Loans [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for Loan Losses, Collectively Evaluated for Impairment	3,312		3,094
Allowance for Loan Losses, Total	3,312	3,600	3,094	1,903	1,731	1,607
Recorded Investment in Loans, Collectively Evaluated for Impairment	1,839,981		1,614,033
Recorded Investment in Loans, Total	1,839,981		1,614,033
Commercial Real Estate [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for Loan Losses, Individually Evaluated for Impairment			722
Allowance for Loan Losses, Collectively Evaluated for Impairment	1,027		641
Allowance for Loan Losses, Total	1,027	932	1,363	504	512	264
Recorded Investment in Loans, Individually Evaluated for Impairment			9,522
Recorded Investment in Loans, Collectively Evaluated for Impairment	78,614		69,189
Recorded Investment in Loans, Total	78,614		78,711
Consumer [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for Loan Losses, Individually Evaluated for Impairment	3		6
Allowance for Loan Losses, Collectively Evaluated for Impairment	100		123
Allowance for Loan Losses, Total	103	105	129	295	107	105
Recorded Investment in Loans, Individually Evaluated for Impairment	3		6
Recorded Investment in Loans, Collectively Evaluated for Impairment	36,146		45,385
Recorded Investment in Loans, Total	36,149		45,391
Home Equity Lines Of Credit [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for Loan Losses, Individually Evaluated for Impairment	149		231
Allowance for Loan Losses, Collectively Evaluated for Impairment	122		140
Allowance for Loan Losses, Total	271	283	371	285	283	290
Recorded Investment in Loans, Individually Evaluated for Impairment	322		413
Recorded Investment in Loans, Collectively Evaluated for Impairment	12,750		14,595
Recorded Investment in Loans, Total	13,072		15,008
Construction And Land [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for Loan Losses, Collectively Evaluated for Impairment	233		232
Allowance for Loan Losses, Total	233	224	232	203	144	78
Recorded Investment in Loans, Collectively Evaluated for Impairment	18,115		12,623
Recorded Investment in Loans, Total	18,115		12,623
Qualitative [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for Loan Losses, Collectively Evaluated for Impairment	2,996		2,187
Allowance for Loan Losses, Total	$ 2,996	$ 2,684	$ 2,187	$ 1,900	$ 1,744	$ 1,454