Mortgage-Backed Securities - Contractual maturity (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Amortized cost by contractual maturity:
Amortized Cost	$ 74,718	$ 68,387
Fair value by contractual maturity:
Fair Value	76,570	69,884
Mortgage-backed securities available for sale
Amortized cost by contractual maturity:
Due after one year through five years	888
Due after five years through ten years	5,120
Due after ten years	81,366
Amortized Cost	87,374	91,219
Fair value by contractual maturity:
Due after one year through five years	883
Due after five years through ten years	5,153
Due after ten years	82,951
Fair Value	$ 88,987	$ 91,478

Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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