Derivative Instruments (Schedule Of Notional Amounts Of Derivative Instruments) (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2012	Dec. 31, 2011
Derivative [Line Items]
Notional Amount of Derivatives	$ 635,772	$ 642,822
Interest Rate Swaps [Member]
Derivative [Line Items]
Notional Amount of Derivatives	490,916	486,207
Interest Rate Caps [Member]
Derivative [Line Items]
Notional Amount of Derivatives	29,236	29,736
Credit Risk Participation Agreements [Member]
Derivative [Line Items]
Notional Amount of Derivatives	41,678	41,414
Foreign Exchange Contracts [Member]
Derivative [Line Items]
Notional Amount of Derivatives	73,942	80,535
Mortgage Loan Commitments [Member]
Derivative [Line Items]
Notional Amount of Derivatives		1,280
Mortgage Loan Forward Sale Contracts [Member]
Derivative [Line Items]
Notional Amount of Derivatives		$ 3,650