Segment Reporting (Schedule Of Information Of Total Assets On Segment Basis) (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Segment Reporting Information [Line Items]
Total assets	$ 25,896,006	$ 24,610,225
Global Wealth Management [Member]
Segment Reporting Information [Line Items]
Total assets	22,071,309	20,675,580
Institutional Group [Member]
Segment Reporting Information [Line Items]
Total assets	3,566,205	3,668,723
Other Segments [Member]
Segment Reporting Information [Line Items]
Total assets	$ 258,492	$ 265,922