Note 8 - Fair Value Measurements - Carrying Value and Estimated Fair Value of Financial Instruments (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Securities available for sale	$ 264,034	$ 254,562
Equity Securities, FV-NI	1,600	1,700
Reported Value Measurement [Member]
Cash and cash equivalents	134,211	51,360
Interest-bearing time deposits	6,843	6,490
Securities available for sale	264,034	254,562
Loans held for sale	6,935	4,176
Loans, net	492,128	466,694
FHLB and other restricted stock	1,988	1,988
Accrued interest receivable	3,320	3,076
Equity Securities, FV-NI	1,620	1,746
Deposits	833,399	722,177
Accrued interest payable	168	210
Estimate of Fair Value Measurement [Member]
Cash and cash equivalents	134,211	51,360
Interest-bearing time deposits	7,176	6,654
Securities available for sale	264,034	254,562
Loans held for sale	7,001	4,243
Loans, net	502,630	482,119
Accrued interest receivable	3,320	3,076
Equity Securities, FV-NI	1,620	1,746
Deposits	835,706	721,729
Accrued interest payable	168	210
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 1 [Member]
Cash and cash equivalents	134,211	51,360
Interest-bearing time deposits	0	0
Securities available for sale	0	0
Loans held for sale	0	0
Loans, net	0	0
Accrued interest receivable	0	0
Equity Securities, FV-NI	1,620	1,746
Deposits	0	0
Accrued interest payable	0	0
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 2 [Member]
Cash and cash equivalents	0	0
Interest-bearing time deposits	7,176	6,654
Securities available for sale	264,034	254,562
Loans held for sale	7,001	4,243
Loans, net	0	0
Accrued interest receivable	3,320	3,076
Equity Securities, FV-NI	0	0
Deposits	0	0
Accrued interest payable	168	210
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 3 [Member]
Cash and cash equivalents	0	0
Interest-bearing time deposits	0	0
Securities available for sale	0	0
Loans held for sale	0	0
Loans, net	502,630	482,119
Accrued interest receivable	0	0
Equity Securities, FV-NI	0	0
Deposits	835,706	721,729
Accrued interest payable	$ 0	$ 0

Represents the fair value of accrued interest receivable.

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Represents the fair value of interest payable.

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No definition available.

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Fair value portion of interest-bearing deposits in other financial institutions for relatively short periods of time including, for example, certificates of deposits, which are presented separately from cash on the balance sheet.

+ References

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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

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
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-Section 45
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-URI http://asc.fasb.org/extlink&oid=121558606&loc=SL82898722-210454

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
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-Section 45
-Paragraph 1
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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.

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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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- Definition

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

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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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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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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-URI http://asc.fasb.org/subtopic&trid=2196772

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