Fair Values Of Assets And Liabilities (Summary Of Changes In Level 3 Assets And Liabilities Measured At Fair Value On A Recurring Basis) (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2015		Mar. 31, 2014
Mortgage Servicing Rights [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning Balance	$ 8,435		$ 8,946
Total net gains (losses) included in Net income	(583)	[1]	(227)	[1]
Ending Balance	7,852		8,719
Municipal
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning Balance	58,953		36,386
Total net gains (losses) included in Other comprehensive income	203		147
Purchases	6,674		3,360
Settlements	(9,781)		(121)
Ending Balance	56,049		39,772
Equity securities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning Balance	23,711		22,163
Total net gains (losses) included in Other comprehensive income	945		1,275
Ending Balance	$ 24,656		$ 23,438

[1] Changes in the balance of mortgage servicing rights are recorded as a component of mortgage banking revenue in non-interest income.