Note 8 - Fair Value Measurements - Carrying Value and Estimated Fair Value of Financial Instruments (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Securities available for sale	$ 313,540	$ 283,502
Equity Securities, FV-NI	1,800	1,600
Reported Value Measurement [Member]
Cash and cash equivalents	205,956	175,888
Interest-bearing time deposits	6,195	6,396
Securities available for sale	313,540	283,502
Loans held for sale	4,331	7,941
Loans, net	482,623	500,331
FHLB and other restricted stock	1,988	1,988
Accrued interest receivable	3,101	3,434
Equity Securities, FV-NI	1,787	1,553
Deposits	940,522	900,461
Accrued interest payable	124	153
Estimate of Fair Value Measurement [Member]
Cash and cash equivalents	205,956	175,888
Interest-bearing time deposits	6,438	6,687
Securities available for sale	313,540	283,502
Loans held for sale	4,408	8,101
Loans, net	489,718	506,207
Accrued interest receivable	3,101	3,434
Equity Securities, FV-NI	1,787	1,553
Deposits	940,906	901,073
Accrued interest payable	124	153
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 1 [Member]
Cash and cash equivalents	205,956	175,888
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	1,787	1,553
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	6,438	6,687
Securities available for sale	313,540	283,502
Loans held for sale	4,408	8,101
Loans, net	0	0
Accrued interest receivable	3,101	3,434
Equity Securities, FV-NI	0	0
Deposits	0	0
Accrued interest payable	124	153
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	489,718	506,207
Accrued interest receivable	0	0
Equity Securities, FV-NI	0	0
Deposits	940,906	901,073
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

No definition available.

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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))
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
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-Section 45
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
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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).

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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
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-SubTopic 10
-URI http://asc.fasb.org/subtopic&trid=2196772

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