Note 5 - Fair Value Measurements - Estimated Fair Values of Financial Instruments (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Securities available-for-sale	$ 672,344	$ 596,999
Accrued income receivable	10,014	11,143
Reported Value Measurement [Member]
Securities available-for-sale	672,344	596,999
Reported Value Measurement [Member] \| Fair Value, Inputs, Level 1 [Member]
Cash and due from banks	23,557	24,819
Interest-bearing deposits	227,159	166,704
Accrued income receivable	10,014	11,143
Securities sold under agreements to repurchase	41,421	37,293
Accrued interest payable	635	829
Reported Value Measurement [Member] \| Fair Value, Inputs, Level 2 [Member]
FHLB and FRB stock	3,427	3,148
Loans receivable, net	1,120,211	1,129,505
Loans held for sale	598	1,621
Deposits	1,842,755	1,716,446
FHLB advances	3,000	3,000
Estimate of Fair Value Measurement [Member]
Securities available-for-sale	672,344	596,999
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 1 [Member]
Cash and due from banks	23,557	24,819
Interest-bearing deposits	227,159	166,704
Accrued income receivable	10,014	11,143
Securities sold under agreements to repurchase	41,421	37,293
Accrued interest payable	635	829
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 2 [Member]
FHLB and FRB stock	3,427	3,148
Loans receivable, net	1,102,667	1,116,352
Loans held for sale	598	1,621
Deposits	1,845,493	1,720,023
FHLB advances	$ 3,080	$ 3,111

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
-Section S99
-Paragraph 1
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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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-Section S99
-Paragraph 1
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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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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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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- Definition

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

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

+ References

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-Publisher FASB
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