Consolidated Statements Of Comprehensive Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Statement of Comprehensive Income [Abstract]
Net income	$ 21,659	$ 81,466	$ 84,471	$ 170,612
Unrealized gains on available-for-sale securities
Before tax	5,068	26,177	96,422	64,452
Tax effect	(1,350)	(6,977)	(25,697)	(17,296)
Net of tax	3,718	19,200	70,725	47,156
Reclassification of net (losses) gains on available-for-sale securities included in net income
Before tax	(341)	523	150	456
Tax effect	92	(140)	(40)	(122)
Net of tax	(249)	383	110	334
Reclassification of amortization of unrealized gains on investment securities transferred to held-to-maturity from available-for-sale
Before tax	46	214	124	358
Tax effect	(12)	(57)	(33)	(98)
Net of tax	34	157	91	260
Net unrealized gains on available-for-sale securities	3,933	18,660	70,524	46,562
Unrealized losses on derivative instruments
Before tax	(2,867)	(22,168)	(41,560)	(27,164)
Tax effect	773	5,918	11,095	7,263
Net unrealized losses on derivative instruments	(2,094)	(16,250)	(30,465)	(19,901)
Foreign currency adjustment
Before tax	6,677	3,232	(7,655)	6,123
Tax effect	(1,510)	(727)	1,677	(1,341)
Net foreign currency adjustment	5,167	2,505	(5,978)	4,782
Total other comprehensive income	7,006	4,915	34,081	31,443
Comprehensive income	$ 28,665	$ 86,381	$ 118,552	$ 202,055