Note 5 - Fair Value of Financial Instruments - Estimated Fair Value of Company's Financial Instruments (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Financial assets:
Securities available for sale	$ 100,939	$ 107,592
Equity securities	110	167
Loans receivable, net	617,645	596,392
Reported Value Measurement [Member]
Financial assets:
Cash and cash equivalents	35,744	44,399
Securities available for sale	100,939	107,592
Equity securities	110	167
Loans held for sale	4,884	3,606
Loans receivable, net	617,645	596,392
Federal Home Loan Bank stock	932	854
Accrued interest receivable	2,236	2,251
Financial liabilities:
Deposits	677,519	673,870
Accrued interest payable	344	420
Commitments to extend credit	522	14
Commitments to sell loans	(81)	(16)
Estimate of Fair Value Measurement [Member]
Financial assets:
Cash and cash equivalents	35,744	44,399
Securities available for sale	100,939	107,592
Equity securities	110	167
Loans held for sale	4,884	3,606
Loans receivable, net	631,431	600,863
Federal Home Loan Bank stock	932	854
Accrued interest receivable	2,236	2,251
Financial liabilities:
Deposits	678,952	673,945
Accrued interest payable	344	420
Commitments to extend credit	522	14
Commitments to sell loans	(81)	(16)
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 1 [Member]
Financial assets:
Cash and cash equivalents	35,744	44,399
Securities available for sale
Equity securities
Loans held for sale
Loans receivable, net
Federal Home Loan Bank stock
Accrued interest receivable
Financial liabilities:
Deposits
Accrued interest payable
Commitments to extend credit
Commitments to sell loans
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 2 [Member]
Financial assets:
Cash and cash equivalents
Securities available for sale	100,939	107,592
Equity securities	110	167
Loans held for sale	4,884	3,606
Loans receivable, net	631,431	600,863
Federal Home Loan Bank stock	932	854
Accrued interest receivable	2,236	2,251
Financial liabilities:
Deposits	678,952	673,945
Accrued interest payable	344	420
Commitments to extend credit
Commitments to sell loans
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 3 [Member]
Financial assets:
Cash and cash equivalents
Securities available for sale
Equity securities
Loans held for sale
Loans receivable, net
Federal Home Loan Bank stock
Accrued interest receivable
Financial liabilities:
Deposits
Accrued interest payable
Commitments to extend credit
Commitments to sell loans
Portion at Other than Fair Value Measurement [Member]
Financial assets:
Cash and cash equivalents
Securities available for sale
Equity securities
Loans held for sale
Loans receivable, net
Federal Home Loan Bank stock
Accrued interest receivable
Financial liabilities:
Deposits
Accrued interest payable
Commitments to extend credit	210,676	178,804
Commitments to sell loans	$ 66,668	$ 10,098

Fair value portion of accrued interest payable.

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Fair value portion of accrued interest receivable.

+ References

No definition available.

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The face amount of financial liabilities related to commitments to sell, which are not recognized in the financial statements (off-balance sheet) because they fail to meet some other criterion for recognition.

+ References

No definition available.

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(6))
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
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-Section 45
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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-Topic 320
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-Section 45
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-Section 50
-Paragraph 2
-Subparagraph (aa)
-URI http://asc.fasb.org/extlink&oid=121645371&loc=d3e27161-111563

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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 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.

+ References

No definition available.

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Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 45
-Paragraph 1A
-URI http://asc.fasb.org/extlink&oid=99377092&loc=SL75136599-209740

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The face amount of financial assets, which are not recognized in the financial statements (off-balance sheet) because they fail to meet some other criterion for recognition.

+ References

No definition available.

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- Definition

Fair value portion of investments in Federal Home Loan Bank (FHLBank) stock.

+ References

No definition available.

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- Definition

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=121593590&loc=d3e4428-111522

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Fair value portion of loans held-for-sale including, but not limited to, mortgage loans and finance receivables.

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