Business Segment Information (Schedule Of Financial Information About Business Segments) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Segment Reporting Information [Line Items]
Revenues	$ 343,831	$ 337,745	$ 678,094	$ 663,189
Expenses	236,456	229,056	470,860	448,071
Operating profit (loss)	107,375	108,689	207,234	215,118
Gain on sale of subsidiary	0	0	2,791	2,791
Segment profit (loss)			210,025	217,909
Private Banks [Member]
Segment Reporting Information [Line Items]
Revenues	114,836	115,333	228,197	226,546
Expenses	102,862	104,727	206,603	203,983
Operating profit (loss)	11,974	10,606	21,594	22,563
Gain on sale of subsidiary	0	0	2,791	2,791
Segment profit (loss)			24,385	25,354
Investment Advisors [Member]
Segment Reporting Information [Line Items]
Revenues	81,883	77,753	158,562	151,768
Expenses	44,721	40,857	89,495	79,916
Operating profit (loss)	37,162	36,896	69,067	71,852
Gain on sale of subsidiary	0	0	0	0
Segment profit (loss)			69,067	71,852
Institutional Investors [Member]
Segment Reporting Information [Line Items]
Revenues	74,674	75,980	147,571	149,528
Expenses	36,550	36,528	71,932	71,739
Operating profit (loss)	38,124	39,452	75,639	77,789
Gain on sale of subsidiary	0	0	0	0
Segment profit (loss)			75,639	77,789
Investment Managers [Member]
Segment Reporting Information [Line Items]
Revenues	70,938	67,280	140,856	132,647
Expenses	46,968	42,141	92,243	82,764
Operating profit (loss)	23,970	25,139	48,613	49,883
Gain on sale of subsidiary	0	0	0	0
Segment profit (loss)			48,613	49,883
Investments In New Businesses [Member]
Segment Reporting Information [Line Items]
Revenues	1,500	1,399	2,908	2,700
Expenses	5,355	4,803	10,587	9,669
Operating profit (loss)	(3,855)	(3,404)	(7,679)	(6,969)
Gain on sale of subsidiary	$ 0	$ 0	0	0
Segment profit (loss)			$ (7,679)	$ (6,969)

Total profit (loss)

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- Definition

Amount before tax of gain (loss) recognized on the sale or disposal of a disposal group. Excludes discontinued operations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=68055307&loc=d3e2443-110228

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=64862545&loc=d3e2941-110230

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Aggregate revenue less cost of goods and services sold or operating expenses directly attributable to the revenue generation activity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1,2)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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Generally recurring costs associated with normal operations except for the portion of these expenses which can be clearly related to production and included in cost of sales or services. Excludes Selling, General and Administrative Expense.

+ References

No definition available.

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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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.

+ References

No definition available.

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