Loans (Net (Charge-Offs)/Recoveries, Segregated By Class Of Loans) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2012	Mar. 31, 2011
Accounts, Notes, Loans and Financing Receivable [Line Items]
Net charge-offs	$ (4,066)	$ (11,445)
Commercial And Industrial, Energy [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Net charge-offs	4
Commercial And Industrial, Other Commercial [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Net charge-offs	(1,675)	(6,830)
Commercial Real Estate, Buildings, Land And Other [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Net charge-offs	(2,360)	(3,165)
Commercial Real Estate, Construction [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Net charge-offs	10	(156)
Consumer Real Estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Net charge-offs	234	(530)
Consumer And Other [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Net charge-offs	$ (279)	$ (764)