Investment Securities - Maturities (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Amortized Cost
Due in one year or less	$ 3,023
Due after one year through five years	2,491
Due after five years through ten years	12,680
Due after ten years or more	16,126
Mortgage-backed, due in monthly installments	20,665
Amortized Cost	54,985	$ 52,294
Fair Value
Due in one year or less	3,018
Due after one year through five years	2,489
Due after five years through ten years	13,139
Due after ten years or more	16,502
Mortgage-backed, due in monthly installments	20,706
Fair Value	$ 55,854	$ 51,300