Bank Loans (Recorded Balances Of Loans and Amount Of Allowance Allocated Based Upon Impairment Method by Portfolio Segment) (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016	Mar. 31, 2016	Dec. 31, 2015
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for Loan Losses, Individually Evaluated for Impairment	$ 3,602	$ 3,375	$ 2,383
Allowance for Loan Losses, Collectively Evaluated for Impairment	47,696	41,788	31,667
Allowance for Loan Losses, Total	51,298	45,163	34,050	$ 29,787
Recorded Investment in Loans, Individually Evaluated for Impairment	28,036	26,934	23,002
Recorded Investment in Loans, Collectively Evaluated for Impairment	5,895,588	5,610,631	3,482,507
Recorded Investment in Loans, Total	5,923,624	5,637,565	3,505,509
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	4,166	2,636	1,306
Allowance for Loan Losses, Total	4,190	2,660	1,330	1,241
Recorded Investment in Loans, Individually Evaluated for Impairment	176	178	704
Recorded Investment in Loans, Collectively Evaluated for Impairment	2,214,180	2,161,222	729,979
Recorded Investment in Loans, Total	2,214,356	2,161,400	730,683
Commercial And Industrial [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for Loan Losses, Individually Evaluated for Impairment	2,453	2,392	1,215
Allowance for Loan Losses, Collectively Evaluated for Impairment	36,336	32,735	26,485
Allowance for Loan Losses, Total	38,789	35,127	27,700	24,748
Recorded Investment in Loans, Individually Evaluated for Impairment	18,010	16,815	12,148
Recorded Investment in Loans, Collectively Evaluated for Impairment	1,812,855	1,693,584	1,283,170
Recorded Investment in Loans, Total	1,830,865	1,710,399	1,295,318
Securities-Based Loans [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for Loan Losses, Collectively Evaluated for Impairment	3,393	3,094	1,605
Allowance for Loan Losses, Total	3,393	3,094	1,605	1,607
Recorded Investment in Loans, Collectively Evaluated for Impairment	1,728,516	1,614,033	1,345,719
Recorded Investment in Loans, Total	1,728,516	1,614,033	1,345,719
Commercial Real Estate [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for Loan Losses, Individually Evaluated for Impairment	972	722	981
Allowance for Loan Losses, Collectively Evaluated for Impairment	646	641	308
Allowance for Loan Losses, Total	1,618	1,363	1,289	264
Recorded Investment in Loans, Individually Evaluated for Impairment	9,522	9,522	9,809
Recorded Investment in Loans, Collectively Evaluated for Impairment	69,000	69,189	73,464
Recorded Investment in Loans, Total	78,522	78,711	83,273
Consumer [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for Loan Losses, Individually Evaluated for Impairment	5	6	14
Allowance for Loan Losses, Collectively Evaluated for Impairment	102	123	70
Allowance for Loan Losses, Total	107	129	84	105
Recorded Investment in Loans, Individually Evaluated for Impairment	5	6	18
Recorded Investment in Loans, Collectively Evaluated for Impairment	42,851	45,385	31,018
Recorded Investment in Loans, Total	42,856	45,391	31,036
Home Equity Lines Of Credit [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for Loan Losses, Individually Evaluated for Impairment	148	231	149
Allowance for Loan Losses, Collectively Evaluated for Impairment	137	140	118
Allowance for Loan Losses, Total	285	371	267	290
Recorded Investment in Loans, Individually Evaluated for Impairment	323	413	323
Recorded Investment in Loans, Collectively Evaluated for Impairment	14,255	14,595	12,188
Recorded Investment in Loans, Total	14,578	15,008	12,511
Construction And Land [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for Loan Losses, Collectively Evaluated for Impairment	437	232	118
Allowance for Loan Losses, Total	437	232	118	78
Recorded Investment in Loans, Collectively Evaluated for Impairment	13,931	12,623	6,969
Recorded Investment in Loans, Total	13,931	12,623	6,969
Qualitative [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for Loan Losses, Collectively Evaluated for Impairment	2,479	2,187	1,657
Allowance for Loan Losses, Total	$ 2,479	$ 2,187	$ 1,657	$ 1,454

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