Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Statement of Comprehensive Income [Abstract]
Net income	$ 355,697	$ 343,166	$ 257,682
Unrealized gains (losses) on available-for-sale securities
Before tax	79,702	(27,408)	22,123
Tax effect	(21,361)	7,354	(7,706)
Net of tax	58,341	(20,054)	14,417
Reclassification of net gains on available-for-sale securities included in net income
Before tax	899	33	45
Tax effect	(241)	(9)	(18)
Net of tax	658	24	27
Reclassification of amortization of unrealized gains on investment securities transferred to held-to-maturity from available-for-sale
Before tax	479	89	1,479
Tax effect	(131)	(24)	(585)
Net of tax	348	65	894
Net unrealized gains (losses) on available-for-sale securities	57,335	(20,143)	13,496
Unrealized (losses) gains on derivative instruments
Before tax	(28,685)	(1,160)	4,958
Tax effect	7,687	310	(1,959)
Net unrealized (losses) gains on derivative instruments	(20,998)	(850)	2,999
Foreign currency translation adjustment
Before tax	7,483	(12,216)	9,446
Tax effect	(1,626)	3,026	(2,448)
Net foreign currency translation adjustment	5,857	(9,190)	6,998
Total other comprehensive income (loss)	42,194	(30,183)	23,493
Comprehensive income	$ 397,891	$ 312,983	$ 281,175