Interest Rate Contracts (Schedule Of Fair Values Of Derivative Instruments) (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2012	Dec. 31, 2011
Derivative [Line Items]
Total derivative assets	$ 22	$ 699
Total derivative liabilities	107,471	98,417
Interest Rate Contracts [Member]
Derivative [Line Items]
Total derivative assets	22	699
Total derivative liabilities	107,471	98,417
Interest Rate Contracts [Member] | Derivatives Designated As Hedges [Member]
Derivative [Line Items]
Derivative asset, fair value	5	55
Derivative liability, fair value	107,471	97,774
Interest Rate Contracts [Member] | Derivatives Not Designated As Hedges [Member]
Derivative [Line Items]
Derivative asset, fair value	17	644
Derivative liability, fair value	$ 0	$ 643