Investment Securities - Mortgage-Backed Securities (Details)	6 Months Ended
Jun. 30, 2020 USD ($)
Schedule of Investments [Line Items]
Fair market value of received mortgage-backed securities	$ 9,800,000
Mortgage servicing assets	78,000
Net gain recognized on the securitization	377,000
Fixed-rate mortgage loans
Schedule of Investments [Line Items]
Book value	9,400,000
Net gain recognized on the securitization	$ 377,000

Face (par) amount of debt instrument at time of issuance.

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