Loans Receivable and Allowance for Loan Losses, Summary of Loans Receivable (Details)	12 Months Ended
Dec. 31, 2019 USD ($) item	Dec. 31, 2018 USD ($)
Summary of loans receivable [Abstract]
Total loans receivable	$ 648,432,000	$ 685,374,000
Unearned loan fees	(2,747,000)	(3,025,000)
Loans receivable	645,685,000	682,349,000
Loans pledged as collateral	158,900,000
Federal National Mortgage Association [Member]
Summary of loans receivable [Abstract]
Mortgage loans serviced	25,900,000
Federal Home Loan Mortgage Corporation
Summary of loans receivable [Abstract]
Mortgage loans serviced	13,000,000
Residential Mortgage [Member]
Summary of loans receivable [Abstract]
Total loans receivable	269,654,000	276,389,000
Loans receivable	$ 268,152,000	274,759,000
Allowance allocated increased (decreased)		600,000
Loan to value ratio	80.00%
Residential Mortgage [Member] \| Minimum [Member]
Summary of loans receivable [Abstract]
Number of dwelling units \| item	1
Residential Mortgage [Member] \| Maximum [Member]
Summary of loans receivable [Abstract]
Number of dwelling units \| item	4
Commercial [Member]
Summary of loans receivable [Abstract]
Total loans receivable	$ 43,127,000	35,884,000
Loans receivable	43,127,000	35,884,000
Allowance allocated increased (decreased)		2,200,000
Commercial Real Estate [Member]
Summary of loans receivable [Abstract]
Total loans receivable	229,257,000	244,088,000
Loans receivable	228,012,000	242,693,000
Allowance allocated increased (decreased)		2,700,000
ADC [Member]
Summary of loans receivable [Abstract]
Total loans receivable	92,822,000	114,540,000
Loans receivable	92,822,000	114,540,000
Allowance allocated increased (decreased)		1,100,000
Home Equity/2nds [Member]
Summary of loans receivable [Abstract]
Total loans receivable	12,031,000	13,386,000
Loans receivable	$ 12,031,000	13,386,000
Home Equity/2nds [Member] \| Minimum [Member]
Summary of loans receivable [Abstract]
Number of dwelling units \| item	1
Home Equity/2nds [Member] \| Maximum [Member]
Summary of loans receivable [Abstract]
Number of dwelling units \| item	4
Consumer [Member]
Summary of loans receivable [Abstract]
Total loans receivable	$ 1,541,000	1,087,000
Loans receivable	$ 1,541,000	$ 1,087,000

The number of dwelling units commonly found in residential collateralized loans.

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- Definition

A lending risk assessment ratio that financial institutions and others lenders examine before approving a mortgage.

+ References

No definition available.

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- Definition

Loans serviced not included in the accompanying consolidated statements of financial condition, excluding mortgage loans held for sale are sold either with the mortgage servicing rights released or retained by the bank.

+ References

No definition available.

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- References

No definition available.

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- Definition

Amount of increase (decrease) of allowance reserve for credit loss.

+ References

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- Definition

Amount of deferred interest and fee income, unamortized costs incurred to originate loans and leases, unamortized loan commitments and loan syndication fees, and premiums over or discounts from face amounts of acquired loans. Excludes amounts for loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

+ References

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- Definition

Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

Carrying amount as of the balance sheet date of loans that have been pledged as collateral for borrowings. If the secured party has the right by contract or custom to sell or re-pledge the collateral, then the debtor reclassifies that asset and report that asset in its statement of financial position separately from other assets not so encumbered.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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