Note 11 - Fair Values of Financial Instruments - Carrying Value and Estimated Value of Financial Instruments (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Mortgage-backed securities	$ 201,740	$ 201,322
Reported Value Measurement [Member]
Securities held-to-maturity	402,237	406,590
Mortgage-backed securities	201,740	201,322
Net LHFI	561,223	580,327
Deposits	1,115,826	1,126,402
Securities sold under agreement to repurchase	98,532	127,574
Short-term borrowings	1,725
Borrowings on secured line of credit	18,000	18,000
Reported Value Measurement [Member] \| Cash [Member]
Cash and due from banks	15,600	26,948
Reported Value Measurement [Member] \| Interest-Bearing Deposits [Member]
Cash and due from banks	606	1,646
Estimate of Fair Value Measurement [Member]
Securities held-to-maturity	375,952	375,292
Mortgage-backed securities	201,740	201,322
Net LHFI	521,259	541,173
Deposits	1,116,972	1,126,381
Securities sold under agreement to repurchase	98,532	127,574
Short-term borrowings	1,725
Borrowings on secured line of credit	18,000	18,000
Estimate of Fair Value Measurement [Member] \| Cash [Member]
Cash and due from banks	15,600	26,948
Estimate of Fair Value Measurement [Member] \| Interest-Bearing Deposits [Member]
Cash and due from banks	606	1,646
Fair Value, Inputs, Level 1 [Member] \| Estimate of Fair Value Measurement [Member]
Securities held-to-maturity	0	0
Mortgage-backed securities	0	0
Net LHFI	0	0
Deposits	929,637	947,479
Securities sold under agreement to repurchase	98,532	127,574
Short-term borrowings	1,725
Borrowings on secured line of credit	18,000	18,000
Fair Value, Inputs, Level 1 [Member] \| Estimate of Fair Value Measurement [Member] \| Cash [Member]
Cash and due from banks	15,600	26,948
Fair Value, Inputs, Level 1 [Member] \| Estimate of Fair Value Measurement [Member] \| Interest-Bearing Deposits [Member]
Cash and due from banks	606	1,646
Fair Value, Inputs, Level 2 [Member] \| Estimate of Fair Value Measurement [Member]
Securities held-to-maturity	375,952	375,292
Mortgage-backed securities	201,740	201,322
Net LHFI	0	0
Deposits	187,335	178,902
Securities sold under agreement to repurchase	0	0
Short-term borrowings	0
Borrowings on secured line of credit	0	0
Fair Value, Inputs, Level 2 [Member] \| Estimate of Fair Value Measurement [Member] \| Cash [Member]
Cash and due from banks	0	0
Fair Value, Inputs, Level 2 [Member] \| Estimate of Fair Value Measurement [Member] \| Interest-Bearing Deposits [Member]
Cash and due from banks	0	0
Fair Value, Inputs, Level 3 [Member] \| Estimate of Fair Value Measurement [Member]
Securities held-to-maturity	0	0
Mortgage-backed securities	0	0
Net LHFI	521,259	541,173
Deposits	0	0
Securities sold under agreement to repurchase	0	0
Short-term borrowings	0
Borrowings on secured line of credit	0	0
Fair Value, Inputs, Level 3 [Member] \| Estimate of Fair Value Measurement [Member] \| Cash [Member]
Cash and due from banks	0	0
Fair Value, Inputs, Level 3 [Member] \| Estimate of Fair Value Measurement [Member] \| Interest-Bearing Deposits [Member]
Cash and due from banks	0	0
Fair Value, Nonrecurring [Member]
Impaired loans	1,950	2,074
Total	1,950	2,074
Fair Value, Nonrecurring [Member] \| Fair Value, Inputs, Level 1 [Member]
Impaired loans	0	0
Total	0	0
Fair Value, Nonrecurring [Member] \| Fair Value, Inputs, Level 2 [Member]
Impaired loans	0	0
Total	0	0
Fair Value, Nonrecurring [Member] \| Fair Value, Inputs, Level 3 [Member]
Impaired loans	1,950	2,074
Total	$ 1,950	$ 2,074

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

No definition available.

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- Definition

Fair value portion of impaired loans.

+ References

No definition available.

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- Definition

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482106/820-10-50-2

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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
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (aa)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-2

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481830/320-10-45-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(6))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479853/942-210-S99-1

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 30
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479130/326-30-45-1

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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.

+ Details

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- Definition

Fair value of the amount outstanding under the credit facility.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 825
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 10
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482907/825-10-50-10

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Period Type:	instant

- Definition

Fair value portion of contractual arrangement with a lender under which borrowings can be made up to a specific amount at any point in time.

+ References

No definition available.

+ Details

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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
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Publisher FASB
-URI https://asc.fasb.org//310-10/tableOfContent

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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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 825
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 10
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482907/825-10-50-10

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