Note 5 - Fair Value Measurements - Estimated Fair Values of Financial Instruments (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Securities available-for-sale	$ 828,389	$ 831,003
Accrued income receivable	9,478	10,124
FHLB advances and other borrowings	3,994	3,071
Reported Value Measurement [Member]
Securities available-for-sale	828,389	831,003
Estimate of Fair Value Measurement [Member]
Securities available-for-sale	828,389	831,003
Fair Value, Inputs, Level 1 [Member] \| Reported Value Measurement [Member]
Cash and cash equivalents	74,678	89,129
Accrued income receivable	9,478	10,124
Securities sold under agreements to repurchase	35,666	39,851
Accrued interest payable	299	353
Fair Value, Inputs, Level 1 [Member] \| Estimate of Fair Value Measurement [Member]
Cash and cash equivalents	74,678	89,129
Accrued income receivable	9,478	10,124
Securities sold under agreements to repurchase	35,666	39,851
Accrued interest payable	299	353
Fair Value, Inputs, Level 2 [Member]
Loans held for sale	473	0
Fair Value, Inputs, Level 2 [Member] \| Reported Value Measurement [Member]
Interest-bearing time deposits	14,677	16,922
FHLB and FRB stock	3,201	3,422
Loans receivable	1,140,609	1,144,108
Deposits	1,926,140	1,878,019
Fair Value, Inputs, Level 2 [Member] \| Estimate of Fair Value Measurement [Member]
Interest-bearing time deposits	14,677	16,922
FHLB and FRB stock	3,201	3,422
Loans receivable	1,099,249	1,112,684
Deposits	$ 1,926,942	$ 1,880,137

Represents the fair value of FHLB and FRB stock, as of the balance sheet date.

No definition available.

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- Definition

The fair value disclosure of interest bearing deposits.

+ 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
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- Definition

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.

+ References

No definition available.

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- Definition

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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- Definition

Fair value portion of borrowing from Federal Home Loan Bank (FHLBank).

+ References

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- Definition

Amount of interest payable on debt, including, but not limited to, trade payables.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

Carrying amount as of the balance sheet date of interest earned but not received. Also called accrued interest or accrued interest receivable.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
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- Definition

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

+ References

No definition available.

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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.

+ References

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- Definition

Fair value portion of securities that an entity sells and agrees to repurchase at a specified date for a specified price.

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-Publisher FASB
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