Business Segment Information (Schedule Of Financial Information About Business Segments) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016
Segment Reporting Information [Line Items]
Revenues	$ 359,984	$ 334,263
Expenses	251,862	234,404
Operating profit (loss)	108,122	99,859
Gain on sale of subsidiary	0	2,791
Segment profit (loss)	108,122	102,650
Private Banks [Member]
Segment Reporting Information [Line Items]
Revenues	112,634	113,361
Expenses	108,550	103,741
Operating profit (loss)	4,084	9,620
Gain on sale of subsidiary	0	2,791
Segment profit (loss)	4,084	12,411
Investment Advisors [Member]
Segment Reporting Information [Line Items]
Revenues	88,238	76,679
Expenses	47,539	44,774
Operating profit (loss)	40,699	31,905
Gain on sale of subsidiary	0	0
Segment profit (loss)	40,699	31,905
Institutional Investors [Member]
Segment Reporting Information [Line Items]
Revenues	77,004	72,897
Expenses	38,828	35,382
Operating profit (loss)	38,176	37,515
Gain on sale of subsidiary	0	0
Segment profit (loss)	38,176	37,515
Investment Managers [Member]
Segment Reporting Information [Line Items]
Revenues	80,487	69,918
Expenses	52,065	45,275
Operating profit (loss)	28,422	24,643
Gain on sale of subsidiary	0	0
Segment profit (loss)	28,422	24,643
Investments In New Businesses [Member]
Segment Reporting Information [Line Items]
Revenues	1,621	1,408
Expenses	4,880	5,232
Operating profit (loss)	(3,259)	(3,824)
Gain on sale of subsidiary	0	0
Segment profit (loss)	$ (3,259)	$ (3,824)

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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

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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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