Business Segment Information (Schedule Of Additional Information Pertaining To Business Segments) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Segment Reporting Information [Line Items]
Capital Expenditures	$ 73,881	$ 63,346	$ 55,851
Depreciation	24,044	22,448	22,497
Amortization	42,630	38,679	34,602
Assets	1,588,628	1,542,875
Private Banks [Member]
Segment Reporting Information [Line Items]
Capital Expenditures	41,972	30,883	34,258
Depreciation	12,348	13,393	15,506
Amortization	29,819	24,993	22,379
Assets	451,079	417,890
Investment Advisors [Member]
Segment Reporting Information [Line Items]
Capital Expenditures	13,206	13,783	12,611
Depreciation	3,410	2,507	2,091
Amortization	9,880	9,228	8,234
Assets	138,459	134,371
Institutional Investors [Member]
Segment Reporting Information [Line Items]
Capital Expenditures	5,301	4,575	2,712
Depreciation	1,200	1,041	893
Amortization	1,558	1,430	1,274
Assets	105,443	118,397
Investment Managers [Member]
Segment Reporting Information [Line Items]
Capital Expenditures	10,119	9,505	4,871
Depreciation	4,040	2,917	1,970
Amortization	1,029	954	851
Assets	154,432	134,614
Investments In New Businesses [Member]
Segment Reporting Information [Line Items]
Capital Expenditures	736	2,547	639
Depreciation	2,278	1,983	1,589
Amortization	116	1,846	1,636
Assets	5,355	21,830
Total From Business Segments [Member]
Segment Reporting Information [Line Items]
Capital Expenditures	71,334	61,293	55,091
Depreciation	23,276	21,841	22,049
Amortization	42,402	38,451	34,374
Assets	854,768	827,102
Corporate, Non-Segment [Member]
Segment Reporting Information [Line Items]
Capital Expenditures	2,547	2,053	760
Depreciation	768	607	448
Amortization	228	228	$ 228
Assets	$ 733,860	$ 715,773

The aggregate amount of recurring noncash expense charged against earnings in the period to allocate the cost of assets over their estimated remaining economic lives.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3602-108585

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Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.18)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 03
-Paragraph 12
-Article 7

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Future cash outflow to pay for purchases of fixed assets that have occurred.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4332-108586

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4313-108586

Reference 3: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

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