Note 8 - Fair Value Measurements - Carrying Value and Estimated Fair Value of Financial Instruments (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Securities available for sale	$ 438,168	$ 447,335
Securities held to maturity	6,633	2,004
Equity securities (included in other assets)	1,900
Reported Value Measurement [Member]
Cash and cash equivalents	167,690	172,509
Interest-bearing time deposits	4,588	4,839
Securities available for sale	438,168
Securities held to maturity	7,000	2,000
Loans held for sale	2,044	2,413
Loans, net	505,950	483,287
FHLB and other restricted stock	1,836	1,988
Accrued interest receivable	3,449	3,430
Equity securities (included in other assets)	1,944	1,881
Deposits	1,072,079	1,035,562
Accrued interest payable	75	97
Securities available for sale		447,335
Estimate of Fair Value Measurement [Member]
Cash and cash equivalents	167,690	172,509
Interest-bearing time deposits	4,615	4,965
Securities available for sale	438,168
Securities held to maturity	6,633	2,004
Loans held for sale	2,081	2,459
Loans, net	499,994	481,961
Accrued interest receivable	3,449	3,430
Equity securities (included in other assets)	1,944	1,881
Deposits	1,071,035	1,035,406
Accrued interest payable	75	97
Securities available for sale		447,335
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 1 [Member]
Cash and cash equivalents	167,690	172,509
Interest-bearing time deposits	0	0
Securities available for sale	0
Securities held to maturity	0	0
Loans held for sale	0	0
Loans, net	0	0
Accrued interest receivable	0	0
Equity securities (included in other assets)	1,944	1,881
Deposits	0	0
Accrued interest payable	0	0
Securities available for sale		0
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 2 [Member]
Cash and cash equivalents	0	0
Interest-bearing time deposits	4,615	4,965
Securities available for sale	438,168
Securities held to maturity	6,633	2,004
Loans held for sale	2,081	2,459
Loans, net	0	0
Accrued interest receivable	3,449	3,430
Equity securities (included in other assets)	0	0
Deposits	0	0
Accrued interest payable	75	97
Securities available for sale		447,335
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
Securities held to maturity	0	0
Loans held for sale	0	0
Loans, net	499,994	481,961
Accrued interest receivable	0	0
Equity securities (included in other assets)	0	0
Deposits	1,071,035	1,035,406
Accrued interest payable	$ 0	0
Securities available for sale		$ 0

Represents the fair value of accrued interest receivable.

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Represents the fair value of interest payable.

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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.

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Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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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).

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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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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), classified as current.

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Fair value of investment in debt security measured at amortized cost (held-to-maturity).

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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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