Loans Receivable and Allowance for Loan Losses - Collateral, Sales, Serviced for Others, Directors and Executive Officers (Details)	3 Months Ended
Mar. 31, 2020 USD ($) loan	Mar. 31, 2019 USD ($)	Dec. 31, 2019 USD ($) loan
Accounts, Notes, Loans and Financing Receivable
Loans serviced for others	$ 73,100,000		$ 65,100,000
Fair market value of received mortgage-backed securities	9,800,000
Mortgage servicing assets	78,000
Net gain recognized on the securitization	377,000
Loans serviced for others, securitization for which the company continues to hold the related mortgage-backed securities	46,800,000		$ 37,800,000
Loans serviced for others, amount of contractually specified servicing fees earned	$ 44,000	$ 20,000
Fixed-rate mortgage loans \| Maximum
Accounts, Notes, Loans and Financing Receivable
Loan to value ratio (as a percent)	80.00%
Residential Mortgage Loans Held For Sale
Accounts, Notes, Loans and Financing Receivable
Residential mortgage loans sold, loan amount	$ 2,700,000	2,300,000
Residential mortgage loans sold, recognized gains	$ 30,000	$ 6,000
Number of loans \| loan	2		1
Residential mortgage loans held for sale	$ 681,000		$ 470,000
Fixed-rate mortgage loans
Accounts, Notes, Loans and Financing Receivable
Book value	9,400,000
Net gain recognized on the securitization	$ 377,000

Represents the loan to value ratio.

No definition available.

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- Definition

Represents the number of mortgage loans outstanding.

+ References

No definition available.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Principal amount of transferred financial assets in which the transferor has continuing involvement with the assets underlying the transaction. Continuing involvement includes, but is not limited to, servicing, recourse, and restrictions on transferor's interests in transferred financial assets.

+ References

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-Publisher FASB
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- Definition

All amounts that, per contract, are due to the servicer in exchange for servicing the financial asset and would no longer be received by a servicer if the beneficial owners of the serviced assets (or their trustees or agents) were to exercise their actual or potential authority under the contract to shift the servicing to another servicer. Depending on the servicing contract, those fees may include some or all of the difference between the interest rate collected on the asset being serviced and the rate to be paid to the beneficial owners of the asset.

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- Definition

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

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- Definition

A gain (loss) realized on a transfer, accounted for as a sale, of all or a portion of financial assets in which the transferor surrenders control and receives consideration other than a beneficial interest in the assets transferred. Reflects the amount of sales proceeds in excess of, or deficient from, the sum of the carrying amounts of transferred financial assets plus transaction costs.

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- Definition

Reflects the net positive or negative amount derived from subtracting from net proceeds of sale and the carrying amounts, net of allocated reserves, of financial assets transferred to third parties in transactions that qualify for sales treatment.

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- Definition

The face amount of loans that will be sold to other entities.

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- Definition

Amount, after allowance for bad debt, of deductions to loan receivables held-for-sale that are not part of a disposal group.

+ References

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- Definition

Fair value of securitized, pay-through debt securities collateralized by real estate mortgage loans classified as held-to-maturity.

+ References

No definition available.

+ Details

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- Definition

This is the sum of principal amount outstanding for both securitized and unsecuritized loans of all types.

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- Definition

The price received to sell a servicing asset or price paid to transfer a servicing liability in an orderly transaction between market participants at the measurement date.

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