Mortgage Servicing Rights (Schedule Of Changes In Mortgage Servicing Rights) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended				9 Months Ended
	Sep. 30, 2012		Sep. 30, 2011		Sep. 30, 2012		Sep. 30, 2011
Mortgage Servicing Rights [Abstract]
Balance, beginning of period	$ 22,513		$ 16,350		$ 18,184		$ 14,454
Additions for new mortgage servicing rights capitalized	5,642		1,693		11,923		4,100
Due to changes in model inputs or assumptions, changes in fair value	(2,770)	[1]	(590)	[1]	(3,833)	[1]	(564)	[1]
Other, changes in fair value	(896)	[2]	(841)	[2]	(1,785)	[2]	(1,378)	[2]
Balance, end of period	$ 24,489		$ 16,612		$ 24,489		$ 16,612

[1] Principally reflects changes in discount rates and prepayment speed assumptions, which are primarily affected by changes in interest rates.

[2] Represents changes due to collection/realization of expected cash flows over time.