Income Taxes Effective Tax Rate (Details)	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Effective Income Tax Rate, Continuing Operations, Tax Rate Reconciliation [Abstract]
Statutory Tax Rate	35.00%	35.00%	35.00%
Effect Of Tax-Exempt Income	(5.30%)	(5.80%)	(11.20%)
Effect Of Low Income Housing Investments	(4.30%)	(3.30%)	(5.30%)
Bank Owned Life Insurance	(0.60%)	(0.60%)	(1.20%)
State Income Taxes, Net Of Federal Benefit	(4.00%)	0.00%	(0.70%)
Effective Income Tax Rate Reconciliation, Change in Deferred Tax Assets Valuation Allowance	4.60%	0.20%	0.50%
Other, Net	0.50%	0.20%	0.10%
Effective Income Tax Rate	25.90%	25.70%	17.20%