Shareholders' Equity And Earnings Per Share (Components Of Other Comprehensive Income (Loss)) (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Activity Accumulated Other Comprehensive Income [Roll Forward]
Balance	$ 3,691,250	$ 3,267,570
Other comprehensive income (loss) during the period, net of tax, before reclassifications	26,692	29,194
Amount reclassified from accumulated other comprehensive gain (loss) into net income, net of tax	440	(2,563)
Amount reclassified from accumulated other comprehensive loss related to amortization of unrealized gains on investment securities transferred to held-to-maturity from available-for-sale, net of tax	(57)	(103)
Total other comprehensive income	27,075	26,528
Balance	3,700,393	3,371,972
Accumulated Unrealized Gains (Losses) on Securities
Activity Accumulated Other Comprehensive Income [Roll Forward]
Balance	14,982	(42,353)
Other comprehensive income (loss) during the period, net of tax, before reclassifications	67,007	27,956
Amount reclassified from accumulated other comprehensive gain (loss) into net income, net of tax	(359)	49
Amount reclassified from accumulated other comprehensive loss related to amortization of unrealized gains on investment securities transferred to held-to-maturity from available-for-sale, net of tax	(57)	(103)
Total other comprehensive income	66,591	27,902
Balance	81,573	(14,451)
Accumulated Unrealized (Losses) Gains on Derivative Instruments
Activity Accumulated Other Comprehensive Income [Roll Forward]
Balance	(13,141)	7,857
Other comprehensive income (loss) during the period, net of tax, before reclassifications	(29,170)	(1,039)
Amount reclassified from accumulated other comprehensive gain (loss) into net income, net of tax	799	(2,612)
Amount reclassified from accumulated other comprehensive loss related to amortization of unrealized gains on investment securities transferred to held-to-maturity from available-for-sale, net of tax	0	0
Total other comprehensive income	(28,371)	(3,651)
Balance	(41,512)	4,206
Accumulated Foreign Currency Translation Adjustments
Activity Accumulated Other Comprehensive Income [Roll Forward]
Balance	(36,519)	(42,376)
Other comprehensive income (loss) during the period, net of tax, before reclassifications	(11,145)	2,277
Amount reclassified from accumulated other comprehensive gain (loss) into net income, net of tax	0	0
Amount reclassified from accumulated other comprehensive loss related to amortization of unrealized gains on investment securities transferred to held-to-maturity from available-for-sale, net of tax	0	0
Total other comprehensive income	(11,145)	2,277
Balance	(47,664)	(40,099)
Accumulated other comprehensive loss
Activity Accumulated Other Comprehensive Income [Roll Forward]
Balance	(34,678)	(76,872)
Total other comprehensive income	27,075	26,528
Balance	$ (7,603)	$ (50,344)