Business Segment Information (Schedule Of Financial Information About Business Segments) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	9 Months Ended
Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Segment Reporting Information [Line Items]
Revenues	$ 280,655	$ 251,752	$ 827,108	$ 730,887
Expenses	204,314	186,797	606,724	542,337
Gain on sale of subsidiary			22,112
Total profit (loss)			242,496
Private Banks [Member]
Segment Reporting Information [Line Items]
Revenues	97,370	92,076	291,258	268,367
Expenses	95,579	91,209	289,632	263,612
Operating profit (loss)	1,791	867	1,626	4,755
Gain on sale of subsidiary			22,112
Total profit (loss)			23,738
Investment Advisors [Member]
Segment Reporting Information [Line Items]
Revenues	61,393	51,384	175,868	150,227
Expenses	33,768	30,114	98,291	88,440
Operating profit (loss)	27,625	21,270	77,577	61,787
Gain on sale of subsidiary			0
Total profit (loss)			77,577
Institutional Investors [Member]
Segment Reporting Information [Line Items]
Revenues	63,539	58,081	190,385	167,293
Expenses	33,058	29,654	97,595	86,494
Operating profit (loss)	30,481	28,427	92,790	80,799
Gain on sale of subsidiary			0
Total profit (loss)			92,790
Investment Managers [Member]
Segment Reporting Information [Line Items]
Revenues	57,266	49,311	166,542	142,235
Expenses	37,763	32,122	109,432	92,711
Operating profit (loss)	19,503	17,189	57,110	49,524
Gain on sale of subsidiary			0
Total profit (loss)			57,110
Investments In New Businesses [Member]
Segment Reporting Information [Line Items]
Revenues	1,087	900	3,055	2,765
Expenses	4,146	3,698	11,774	11,080
Operating profit (loss)	(3,059)	(2,798)	(8,719)	(8,315)
Gain on sale of subsidiary			0
Total profit (loss)			(8,719)
Operating Segments [Member]
Segment Reporting Information [Line Items]
Operating profit (loss)	$ 76,341	$ 64,955	$ 220,384	$ 188,550

Total profit (loss)

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- Definition

The gain (loss) resulting from the sale of a disposal group that is not a discontinued operation. It is included in income from continuing operations before income taxes in the income statement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 205

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6360339&loc=d3e1361-107760

Reference 2: 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=8077374&loc=d3e2443-110228

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- Definition

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

+ References

+ Details

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- Definition

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.

+ Details

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- Definition

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=26872669&loc=d3e20235-122688

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 1

-Article 5

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