Segment Reporting (Schedule Of Information Of Total Assets On Segment Basis) (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Total assets	$ 8,133,755	$ 6,966,140
Global Wealth Management [Member]
Total assets	5,689,255	5,116,487
Institutional Group [Member]
Total assets	1,997,310	1,447,484
Other [Member]
Total assets	$ 447,190	$ 402,169