Investment Securities (Details 3) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Amortized Cost
Due in one year or less	$ 9,898
Due after one year through five years	300,638
Due after five years through ten years	975,907
Due after ten years	2,345,123
Total securities available-for-sale	3,631,566	$ 3,688,091
Fair Value
Due in one year or less	10,026
Due after one year through five years	309,312
Due after five years through ten years	1,024,183
Due after ten years	2,414,142
Total securities available-for-sale	$ 3,757,663	$ 3,797,187