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	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for Loan Losses, Individually Evaluated for Impairment	$ 2,332		$ 3,375
Allowance for Loan Losses, Collectively Evaluated for Impairment	51,870		41,788
Allowance for Loan Losses, Total	54,202	$ 51,298	45,163	$ 35,866	$ 34,050	$ 29,787
Recorded Investment in Loans, Individually Evaluated for Impairment	14,450		26,934
Recorded Investment in Loans, Collectively Evaluated for Impairment	6,199,363		5,610,631
Recorded Investment in Loans, Total	6,213,813		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	5,545		2,636
Allowance for Loan Losses, Total	5,569	4,190	2,660	1,529	1,330	1,241
Recorded Investment in Loans, Individually Evaluated for Impairment	174		178
Recorded Investment in Loans, Collectively Evaluated for Impairment	2,248,354		2,161,222
Recorded Investment in Loans, Total	2,248,528		2,161,400
Commercial And Industrial [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for Loan Losses, Individually Evaluated for Impairment	2,155		2,392
Allowance for Loan Losses, Collectively Evaluated for Impairment	38,650		32,735
Allowance for Loan Losses, Total	40,805	38,789	35,127	29,816	27,700	24,748
Recorded Investment in Loans, Individually Evaluated for Impairment	13,949		16,815
Recorded Investment in Loans, Collectively Evaluated for Impairment	2,050,103		1,693,584
Recorded Investment in Loans, Total	2,064,052		1,710,399
Securities-Based Loans [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for Loan Losses, Collectively Evaluated for Impairment	3,600		3,094
Allowance for Loan Losses, Total	3,600	3,393	3,094	1,731	1,605	1,607
Recorded Investment in Loans, Collectively Evaluated for Impairment	1,755,592		1,614,033
Recorded Investment in Loans, Total	1,755,592		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	932		641
Allowance for Loan Losses, Total	932	1,618	1,363	512	1,289	264
Recorded Investment in Loans, Individually Evaluated for Impairment			9,522
Recorded Investment in Loans, Collectively Evaluated for Impairment	71,517		69,189
Recorded Investment in Loans, Total	71,517		78,711
Consumer [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for Loan Losses, Individually Evaluated for Impairment	4		6
Allowance for Loan Losses, Collectively Evaluated for Impairment	101		123
Allowance for Loan Losses, Total	105	107	129	107	84	105
Recorded Investment in Loans, Individually Evaluated for Impairment	4		6
Recorded Investment in Loans, Collectively Evaluated for Impairment	42,662		45,385
Recorded Investment in Loans, Total	42,666		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	134		140
Allowance for Loan Losses, Total	283	285	371	283	267	290
Recorded Investment in Loans, Individually Evaluated for Impairment	323		413
Recorded Investment in Loans, Collectively Evaluated for Impairment	13,980		14,595
Recorded Investment in Loans, Total	14,303		15,008
Construction And Land [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for Loan Losses, Collectively Evaluated for Impairment	224		232
Allowance for Loan Losses, Total	224	437	232	144	118	78
Recorded Investment in Loans, Collectively Evaluated for Impairment	17,155		12,623
Recorded Investment in Loans, Total	17,155		12,623
Qualitative [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for Loan Losses, Collectively Evaluated for Impairment	2,684		2,187
Allowance for Loan Losses, Total	$ 2,684	$ 2,479	$ 2,187	$ 1,744	$ 1,657	$ 1,454