Segment Reporting (Schedule Of Operating Information, Segment) (Details) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
		Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Segment Reporting Information [Line Items]
Net revenues	[1]	$ 1,153,136	$ 895,817	$ 2,287,925	$ 1,808,851
Income/(loss) before income taxes		264,025	142,960	491,917	258,066
Global Wealth Management [Member]
Segment Reporting Information [Line Items]
Net revenues	[1]	637,567	505,782	1,269,062	1,088,738
Income/(loss) before income taxes		227,305	156,325	450,536	350,492
Institutional Group [Member]
Segment Reporting Information [Line Items]
Net revenues	[1]	520,811	398,096	1,026,892	730,334
Income/(loss) before income taxes		141,494	83,049	258,682	124,789
Other Segments [Member]
Segment Reporting Information [Line Items]
Net revenues	[1]	(5,242)	(8,061)	(8,029)	(10,221)
Income/(loss) before income taxes		$ (104,774)	$ (96,414)	$ (217,301)	$ (217,215)

[1] No individual client accounted for more than 10 percent of total net revenues for the three and six months ended June 30, 2021 or 2020.