Note 5 - Fair Value Measurements - Estimated Fair Values of Financial Instruments (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Securities available-for-sale	$ 823,897	$ 831,003
Accrued income receivable	9,330	10,124
Reported Value Measurement [Member]
Securities available-for-sale	823,897	831,003
Estimate of Fair Value Measurement [Member]
Securities available-for-sale	823,897	831,003
Fair Value, Inputs, Level 1 [Member] \| Reported Value Measurement [Member]
Cash and cash equivalents	148,332	89,129
Accrued income receivable	9,330	10,124
Securities sold under agreements to repurchase	39,902	39,851
Accrued interest payable	292	353
Fair Value, Inputs, Level 1 [Member] \| Estimate of Fair Value Measurement [Member]
Cash and cash equivalents	148,332	89,129
Accrued income receivable	9,330	10,124
Securities sold under agreements to repurchase	39,902	39,851
Accrued interest payable	292	353
Fair Value, Inputs, Level 2 [Member] \| Reported Value Measurement [Member]
Interest-bearing time deposits	16,419	16,922
FHLB and FRB stock	3,473	3,422
Loans receivable	1,130,077	1,144,108
Deposits	1,959,893	1,878,019
FHLB advances	0	3,000
Fair Value, Inputs, Level 2 [Member] \| Estimate of Fair Value Measurement [Member]
Interest-bearing time deposits	16,419	16,922
FHLB and FRB stock	3,473	3,422
Loans receivable	1,075,680	1,112,684
Deposits	1,961,384	1,880,137
FHLB advances	$ 0	$ 3,071

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

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- Definition

The fair value disclosure of interest bearing deposits.

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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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- 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
-Section S99
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-Subparagraph (SX 210.5-02(3)(a)(4))
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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
-Publisher FASB
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-URI https://asc.fasb.org/subtopic&trid=2196772

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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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