Fair Values of Financial Instruments - Estimated fair values of the Company's financial instruments (Details) - USD ($)	Dec. 31, 2019	Dec. 31, 2018
Financial assets - Carrying Amount
Cash and cash equivalents	$ 13,290,000
Loans receivable, net	282,672,000	$ 296,579,000
Cash value of life insurance	8,023,000	7,860,000
Financial liabilities - Carrying Amount
Deposits.	321,440,000	322,453,000
Long-term debt	0	0
Short-term borrowings	25,000,000	55,000,000
Assets, Fair Value Disclosure [Abstract]
Loans receivable, net	282,583,000	293,175,000
Cash value of life insurance	8,023,000	7,860,000
Financial Liabilities Fair Value Disclosure [Abstract]
Deposits	300,944,000	307,271,000
Short-term debt	25,386,000	$ 55,851,000
Fair Value. \| Level 1
Financial assets - Carrying Amount
Cash and cash equivalents	13,290,000
Financial Liabilities Fair Value Disclosure [Abstract]
Deposits	212,187,000
Fair Value. \| Level 2
Assets, Fair Value Disclosure [Abstract]
Cash value of life insurance	8,023,000
Financial Liabilities Fair Value Disclosure [Abstract]
Deposits	88,757,000
Short-term debt	25,386,000
Fair Value. \| Level 3
Assets, Fair Value Disclosure [Abstract]
Loans receivable, net	$ 282,583,000

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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Fair value portion of the amount that could be realized under a life insurance contract or contracts owned by the entity, commonly known as corporate-owned life insurance (COLI) or bank-owned life insurance (BOLI).

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Carrying amount as of the balance sheet date of amounts which could be received based on the terms of the insurance contract upon surrendering life policies owned by the entity.

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The aggregate of all deposit liabilities held by the entity, including foreign and domestic, interest and noninterest bearing; may include demand deposits, saving deposits, Negotiable Order of Withdrawal (NOW) and time deposits among others.

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Fair value portion of deposit liabilities held by the entity, including, but not limited to, foreign and domestic, interest and noninterest bearing, demand deposits, saving deposits, negotiable orders of withdrawal (NOW) and time deposits.

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Amount after allowance and 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 and loans held for sale.

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Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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