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				6 Months Ended
	Jun. 30, 2012		Jun. 30, 2011		Jun. 30, 2012		Jun. 30, 2011
Investment Securities [Abstract]
Gross gains on sales of securities	$ 5,105		$ 1		$ 5,433		$ 9,422
Gross (losses) on sales of securities	0		0		0		(8,623)
Net gain/(loss) on sales of securities	5,105	[1]	1	[1]	5,433	[1]	799	[1]
Venture capital investments	0	[2]	0	[2]	0	[2]	0	[2]
Net other than temporary impairment ("OTTI") recorded	(40)		0		(40)		0
Total securities gain/(loss), net	5,065		1		5,393		799
Proceeds from sales of available-for-sale securities	$ 8,400				$ 47,493		$ 458,414

[1] Proceeds from sales for the three months ended June 30, 2012 were $8.4 million, and were $47.5 million and $458.4 million for the six months ended June 30, 2012 and 2011, respectively. Proceeds from sales during second quarter 2011 were immaterial.

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