Investment Securities (Schedule Of Realized Gross Gains And Losses On Sale From Available For Sale Portfolio) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2012		Mar. 31, 2011
Investment Securities [Abstract]
Gross gains on sales of securities	$ 328		$ 9,421
Gross (losses) on sales of securities			(8,623)
Net gain/(loss) on sales of securities	328	[1]	798	[1]
Venture capital investments		[2]		[2]
Net other than temporary impairment ("OTTI") recorded
Total securities gain/(loss), net	328		798
Proceeds from sales of available-for-sale securities	$ 39,097		$ 458,314

[1] Proceeds from sales for the three months ended March 31, 2012, and 2011 were $39.1 million, and $458.3 million, respectively.

[2] Generally includes write-offs and/or unrealized fair value adjustments related to venture capital investments.