Residential Mortgage Servicing Rights (Schedule Of Changes In Mortgage Servicing Rights) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Servicing Asset at Fair Value, Amount [Roll Forward]
Balance, beginning of period	$ 142,973	$ 131,817	$ 117,259
Additions for new MSR capitalized	33,445	37,082	35,284
Due to changes in model inputs or assumptions	(1,952)	7,873	(380)
Other	(21,315)	(33,799)	(20,346)
Balance, end of period	$ 153,151	$ 142,973	$ 131,817