Securities Available For Sale (Schedule Of OTTI Related To Historical Estimated Credit Losses On Debt Securities And Changes In Estimated Credit Losses Recognized In Pre-Tax Earnings) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Securities Available For Sale [Abstract]
Estimated credit losses as of beginning of period	$ 5,041	$ 3,938	$ 4,697	$ 3,373
Additions for credit losses for securities on which OTTI has been previously recognized	336	456	622	1,021
Additions for credit losses for securities on which OTTI has not been previously recognized		133	58	133
Reductions for securities paid off during the period	419		419
Estimated credit losses as of June 30	$ 4,958	$ 4,527	$ 4,958	$ 4,527