Segment Reporting (Schedule Of Information Of Total Assets On Segment Basis) (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2012	Dec. 31, 2011
Total assets	$ 5,465,694	$ 4,951,900
Global Wealth Management [Member]
Total assets	3,980,145	3,637,069
Institutional Group [Member]
Total assets	1,182,290	1,028,948
Other [Member]
Total assets	$ 303,259	$ 285,883