Mortgage Servicing Rights (Schedule Of Changes In Mortgage Servicing Rights) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2013		Mar. 31, 2012
Servicing Asset at Fair Value, Amount [Roll Forward]
Balance, beginning of period	$ 27,428		$ 18,184
Additions for new mortgage servicing rights capitalized	6,403		2,948
Due to changes in model inputs or assumptions, changes in fair value	(1,525)	[1]	(94)	[1]
Other, changes in fair value	(209)	[2]	(828)	[2]
Balance, end of period	$ 32,097		$ 20,210

[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.