Segment Reporting (Schedule Of Operating Information, Segment) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2015 item		Mar. 31, 2014
Segment Reporting Information [Line Items]
Number of business segments	3
Net revenues	$ 560,982	[1]	$ 546,756	[1]
Income before income tax expense	70,066		77,429
Net revenues accounted for by individual client, maximum percentage			10.00%
Global Wealth Management [Member]
Segment Reporting Information [Line Items]
Number of businesses within reportable segment	2
Net revenues	329,410	[1]	297,183	[1]
Income before income tax expense	98,847		79,676
Institutional Group [Member]
Segment Reporting Information [Line Items]
Net revenues	238,607	[1]	249,987	[1]
Income before income tax expense	32,331		44,923
Other [Member]
Segment Reporting Information [Line Items]
Net revenues	(7,035)	[1]	(414)	[1]
Income before income tax expense	$ (61,112)		$ (47,170)

[1] No individual client accounted for more than 10 percent of total net revenues for the three months ended March 31, 2015 or 2014.