Consolidated Statements Of Comprehensive Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Statement of Comprehensive Income [Abstract]
Net income	$ 49,111	$ 39,052
Unrealized gains on securities
Before tax	25,176	26,276
Tax effect	(9,988)	(10,331)
Net of tax	15,188	15,945
Reclassification of net gains included in net income
Before tax	1,325	524
Tax effect	(521)	(206)
Net of tax	804	318
Reclassification of amortization of unrealized losses on investment securities transferred to held-to-maturity from available-for-sale
Before tax	(3,425)	0
Tax effect	1,339	0
Net of tax	(2,086)	0
Net unrealized gains on securities	16,470	15,627
Unrealized gains (losses) on derivative instruments
Before tax	478	(561)
Tax effect	(188)	220
Net unrealized gains (losses) on derivative instruments	290	(341)
Foreign currency adjustment
Before tax	8,347	(12,290)
Tax effect	(2,309)	3,245
Net foreign currency adjustment	6,038	(9,045)
Total other comprehensive income	22,798	6,241
Comprehensive income	$ 71,909	$ 45,293