Derivative Financial Instruments (Summary Of Fair Value Of Derivative Financial Instruments) (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2012	Dec. 31, 2011
Derivative [Line Items]
Total derivative assets	$ 40,953	$ 44,415
Total derivative liabilities	33,601	37,332
Designated As Hedging Instruments [Member]
Derivative [Line Items]
Total derivative assets	7,580	7,444
Designated As Hedging Instruments [Member] | Other Assets [Member]
Derivative [Line Items]
Total derivative assets	7,580	7,444
Derivatives Not Designated As Hedging Instruments [Member]
Derivative [Line Items]
Total derivative assets	33,373	36,971
Total derivative liabilities	33,601	37,332
Derivatives Not Designated As Hedging Instruments [Member] | Other Assets [Member] | Interest Rate Contracts [Member]
Derivative [Line Items]
Total derivative assets	33,062	36,755
Derivatives Not Designated As Hedging Instruments [Member] | Other Assets [Member] | Mortgage Contracts [Member]
Derivative [Line Items]
Total derivative assets	311	216
Derivatives Not Designated As Hedging Instruments [Member] | Other Liabilities [Member] | Interest Rate Contracts [Member]
Derivative [Line Items]
Total derivative liabilities	$ 33,601	$ 37,332