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	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Mortgage Servicing Rights
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning Balance	$ 13,382	$ 8,034	$ 9,092	$ 8,435
Total net gains (losses) included in Net income	519	(159)	4,809	(560)
Total net gains (losses) included in Other comprehensive income		0		0
Purchases		0		0
Issuances	0	0	0	0
Settlements		0		0
Net transfers into/(out of) Level 3	0	0	0	0
Ending Balance	13,901	7,875	13,901	7,875
Municipal
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning Balance	69,812	58,572	68,613	58,953
Total net gains (losses) included in Net income		0		0
Total net gains (losses) included in Other comprehensive income	(241)	223	(141)	(287)
Purchases	2,184	10,405	6,458	21,254
Issuances	0	0	0	0
Sales	0	0	0	0
Settlements	(4,547)	(799)	(7,722)	(11,519)
Net transfers into/(out of) Level 3		0		0
Ending Balance	67,208	68,401	67,208	68,401
Equity securities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning Balance	25,187	24,996	25,199	23,711
Total net gains (losses) included in Net income		0		0
Total net gains (losses) included in Other comprehensive income	0	(480)	(12)	805
Purchases		0		0
Issuances	0	0	0	0
Sales	(25,187)		(25,187)
Settlements		0		0
Net transfers into/(out of) Level 3	0	0	0	0
Ending Balance	$ 0	$ 24,516	$ 0	$ 24,516