Investment Securities (Proceeds From Sales Of Securities And Components Of Investment Securities Gains And Losses) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2012		Mar. 31, 2011
Investment [Line Items]
Proceeds from sales of available for sale securities	$ 4,951		$ 11,202
Proceeds from sales of non-marketable securities	2,035
Total proceeds	6,986	[1]	11,202	[1]
Other-than-temporary impairment recognized on debt securities	(320)		(274)
Investment securities gains, net	4,040	[1]	1,327	[1]
Available For Sale [Member]
Investment [Line Items]
Gains realized on sales	342		176
Other-than-temporary impairment recognized on debt securities	(320)		(274)
Losses realized on sales	(200)
Non-Marketable [Member]
Investment [Line Items]
Gains realized on sales	93
Fair value adjustments, net	$ 4,125		$ 1,425

[1] Available for sale and non-marketable securities