Shareholders' Equity And Earnings Per Share (Components Of Other Comprehensive Income (Loss)) (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Activity Accumulated Other Comprehensive Income [Roll Forward]
Balance at beginning of period	$ (39,910)	$ (31,091)	$ (62,708)	$ (37,332)
Other comprehensive income (loss) during the period, net of tax, before reclassifications	3,514	(31,072)	24,591	(24,765)
Amount reclassified from accumulated other comprehensive income (loss), net of tax	(370)	292	(735)	226
Amount reclassified from accumulated other comprehensive income (loss) related to amortization of unrealized losses on investment securities transferred to held-to-maturity from available-for-sale, net of tax	2,326	0	4,412	0
Other comprehensive income, net of tax	5,470	(30,780)	28,268	(24,539)
Balance at end of period	(34,440)	(61,871)	(34,440)	(61,871)
Accumulated Net Investment Gain (Loss) Attributable to Parent [Member]
Activity Accumulated Other Comprehensive Income [Roll Forward]
Balance at beginning of period	(1,204)	6,094	(17,674)	(9,533)
Other comprehensive income (loss) during the period, net of tax, before reclassifications	3,724	(32,441)	18,912	(16,496)
Amount reclassified from accumulated other comprehensive income (loss), net of tax	(875)	14	(1,679)	(304)
Amount reclassified from accumulated other comprehensive income (loss) related to amortization of unrealized losses on investment securities transferred to held-to-maturity from available-for-sale, net of tax	2,326	0	4,412	0
Other comprehensive income, net of tax	5,175	(32,427)	21,645	(16,800)
Balance at end of period	3,971	(26,333)	3,971	(26,333)
Accumulated Unrealized Losses on Derivative Instruments
Activity Accumulated Other Comprehensive Income [Roll Forward]
Balance at beginning of period	(1,903)	(2,858)	(2,193)	(2,517)
Other comprehensive income (loss) during the period, net of tax, before reclassifications	(822)	(147)	(971)	(740)
Amount reclassified from accumulated other comprehensive income (loss), net of tax	505	278	944	530
Amount reclassified from accumulated other comprehensive income (loss) related to amortization of unrealized losses on investment securities transferred to held-to-maturity from available-for-sale, net of tax	0	0	0	0
Other comprehensive income, net of tax	(317)	131	(27)	(210)
Balance at end of period	(2,220)	(2,727)	(2,220)	(2,727)
Accumulated Foreign Currency Adjustment Attributable to Parent [Member]
Activity Accumulated Other Comprehensive Income [Roll Forward]
Balance at beginning of period	(36,803)	(34,327)	(42,841)	(25,282)
Other comprehensive income (loss) during the period, net of tax, before reclassifications	612	1,516	6,650	(7,529)
Amount reclassified from accumulated other comprehensive income (loss), net of tax	0	0	0	0
Amount reclassified from accumulated other comprehensive income (loss) related to amortization of unrealized losses on investment securities transferred to held-to-maturity from available-for-sale, net of tax	0	0	0	0
Other comprehensive income, net of tax	612	1,516	6,650	(7,529)
Balance at end of period	$ (36,191)	$ (32,811)	$ (36,191)	$ (32,811)