Note 18 - Fair Values of Financial Instruments - Carrying Value and Estimated Value of Financial Instruments (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Available-for-sale, fair value	$ 201,322	$ 631,835
Reported Value Measurement [Member]
Securities held-to-maturity	406,590	0
Available-for-sale, fair value	201,322	631,835
Net loans	580,327	567,334
Deposits	1,126,402	1,111,892
Securities Sold under Agreement to Repurchase	127,574	112,760
Borrowings on secured line of credit	18,000
Borrowings on secured line of credit		18,000
Reported Value Measurement [Member] \| Cash [Member]
Cash and cash equivalents, fair value	26,948	10,673
Reported Value Measurement [Member] \| Interest-Bearing Deposits [Member]
Cash and cash equivalents, fair value	1,646	68,563
Estimate of Fair Value Measurement [Member]
Securities held-to-maturity	375,292	0
Available-for-sale, fair value	201,322	631,835
Net loans	541,173	554,351
Deposits	1,126,381	1,112,323
Securities Sold under Agreement to Repurchase	127,574	112,760
Borrowings on secured line of credit	18,000
Borrowings on secured line of credit		18,000
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 1 [Member]
Securities held-to-maturity	0	0
Available-for-sale, fair value	0	0
Net loans	0	0
Deposits	947,479	881,733
Securities Sold under Agreement to Repurchase	127,574	112,760
Borrowings on secured line of credit	18,000
Borrowings on secured line of credit		18,000
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 2 [Member]
Securities held-to-maturity	375,292	0
Available-for-sale, fair value	201,322	631,835
Net loans	0	0
Deposits	178,902	230,590
Securities Sold under Agreement to Repurchase	0	0
Borrowings on secured line of credit	0
Borrowings on secured line of credit		0
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 3 [Member]
Securities held-to-maturity	0	0
Available-for-sale, fair value	0	0
Net loans	541,173	554,351
Deposits	0	0
Securities Sold under Agreement to Repurchase	0	0
Borrowings on secured line of credit	0
Borrowings on secured line of credit		0
Estimate of Fair Value Measurement [Member] \| Cash [Member]
Cash and cash equivalents, fair value	26,948	10,673
Estimate of Fair Value Measurement [Member] \| Cash [Member] \| Fair Value, Inputs, Level 1 [Member]
Cash and cash equivalents, fair value	26,948	10,673
Estimate of Fair Value Measurement [Member] \| Cash [Member] \| Fair Value, Inputs, Level 2 [Member]
Cash and cash equivalents, fair value	0	0
Estimate of Fair Value Measurement [Member] \| Cash [Member] \| Fair Value, Inputs, Level 3 [Member]
Cash and cash equivalents, fair value	0	0
Estimate of Fair Value Measurement [Member] \| Interest-Bearing Deposits [Member]
Cash and cash equivalents, fair value	1,646	68,563
Estimate of Fair Value Measurement [Member] \| Interest-Bearing Deposits [Member] \| Fair Value, Inputs, Level 1 [Member]
Cash and cash equivalents, fair value	1,646	68,563
Estimate of Fair Value Measurement [Member] \| Interest-Bearing Deposits [Member] \| Fair Value, Inputs, Level 2 [Member]
Cash and cash equivalents, fair value	0	0
Estimate of Fair Value Measurement [Member] \| Interest-Bearing Deposits [Member] \| Fair Value, Inputs, Level 3 [Member]
Cash and cash equivalents, fair value	$ 0	$ 0

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

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
-Subparagraph (SX 210.9-03(6))
-URI https://asc.fasb.org/extlink&oid=126897435&loc=d3e534808-122878

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 45
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=124258926&loc=SL82898722-210454

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=124260329&loc=d3e26610-111562

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-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (aa)
-URI https://asc.fasb.org/extlink&oid=126970911&loc=d3e27161-111563

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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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-URI https://asc.fasb.org/extlink&oid=123594938&loc=d3e13433-108611

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- 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.

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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
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-URI https://asc.fasb.org/subtopic&trid=2196772

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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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-URI https://asc.fasb.org/extlink&oid=123594938&loc=d3e13433-108611

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