Note 5 - Allowances for Loan Losses - Troubled Debt Restructurings (Details) $ in Thousands	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Number of Loans	0	1
Troubled debt restructurings, accrual status	$ 0	$ 4,530
Troubled debt restructurings, non-accrual status	0	0
Troubled debt restructurings	$ 0	$ 4,530
Commercial Real Estate Portfolio Segment [Member]
Number of Loans	0	1
Troubled debt restructurings, accrual status	$ 0	$ 4,530
Troubled debt restructurings, non-accrual status	0	0
Troubled debt restructurings	$ 0	$ 4,530
Construction and Land Development Portfolio Segment [Member]
Number of Loans	0	0
Troubled debt restructurings, accrual status	$ 0	$ 0
Troubled debt restructurings, non-accrual status	0	0
Troubled debt restructurings	$ 0	$ 0
Commercial Portfolio Segment [Member]
Number of Loans	0	0
Troubled debt restructurings, accrual status	$ 0	$ 0
Troubled debt restructurings, non-accrual status	0	0
Troubled debt restructurings	$ 0	$ 0
Owner Occupied Real Estate [Member]
Number of Loans	0	0
Troubled debt restructurings, accrual status	$ 0	$ 0
Troubled debt restructurings, non-accrual status	0	0
Troubled debt restructurings	$ 0	$ 0
Consumer Portfolio Segment [Member]
Number of Loans	0	0
Troubled debt restructurings, accrual status	$ 0	$ 0
Troubled debt restructurings, non-accrual status	0	0
Troubled debt restructurings	$ 0	$ 0
Residential Portfolio Segment [Member]
Number of Loans	0	0
Troubled debt restructurings, accrual status	$ 0	$ 0
Troubled debt restructurings, non-accrual status	0	0
Troubled debt restructurings	$ 0	$ 0
Paycheck Protection Program CARES Act [Member]
Number of Loans	0	0
Troubled debt restructurings, accrual status	$ 0	$ 0
Troubled debt restructurings, non-accrual status	0	0
Troubled debt restructurings	$ 0	$ 0

Cumulative number of financing receivables that have been modified by troubled debt restructurings.

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- Definition

Recorded investment in financing receivables that have undergone troubled debt restructuring and are accruing.

+ References

No definition available.

+ Details

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- Definition

Recorded investment in financing receivables that have undergone troubled debt restructuring and are not accruing.

+ References

No definition available.

+ Details

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- Definition

Amount of financing receivable modified as troubled debt restructuring.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI https://asc.fasb.org/extlink&oid=123577603&loc=SL6953676-111524

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
-Section 50
-Paragraph 4
-URI https://asc.fasb.org/extlink&oid=121585226&loc=d3e18845-111554

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