Securities - Schedule of AFS Debt Securities, By Maturity Date (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Amortized Cost
Within one year	$ 585
After one year but within five years	37,058
After five years but within ten years	49,938
After ten years	317,792
Amortized Cost	405,373	$ 335,603
Fair Value
Within one year	596
After one year but within five years	37,779
After five years but within ten years	51,395
After ten years	323,476
Fair Value	$ 413,246