Consolidated Statements Of Comprehensive Income (Loss) (Parenthetical) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Consolidated Statements Of Comprehensive Income (Loss) [Abstract]
Reclassification adjustment for impairments realized in net income investment securities transferred to held to maturity, tax benefit			$ 1,716
Amortization of unrealized losses on investment securities transferred to held to maturity, tax benefit			70
Reclassification adjustment for net gains realized in earnings, tax expense	3,094	930	3,431
Unrealized (losses) gains related to factors other than credit, tax expense (benefit)	34	(150)	1,080
Reclassification adjustment for impairments realized in net income, tax benefit	108	137	307
Accretion of unrealized losses related to factors other than credit to investment securities held to maturity, tax benefit	$ 66	$ 115	$ 120