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Note 2 - Securities (Details Textual) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2021 USD ($)	Dec. 31, 2020 USD ($)
Weighted Average Re-pricing Term (Year)	5 years 3 months 18 days	3 years 6 months
Proceeds from Sale of Held-to-maturity Securities	$ 0
Other Assets [Member]
Equity Securities without Readily Determinable Fair Value, Amount	$ 454	$ 529
US Agency and Mortgage-backed Securities [Member]
Debt Securities, Available-for-sale, Unrealized Loss Position, Number of Positions	42	7
Available-for-Sale Securities, Number of Securities	123	101
Municipal Bonds [Member]
Debt Securities, Available-for-sale, Unrealized Loss Position, Number of Positions	2	1
Available-for-Sale Securities, Number of Securities	4	84
US States and Political Subdivisions Debt Securities [Member]
Debt Securities, Available-for-sale, Unrealized Loss Position, Number of Positions	25
Available-for-Sale Securities, Number of Securities	110

X

- Definition

The number of investment positions in available-for-sale investments.

+ References

No definition available.

+ Details

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X

- Definition

The weighted average period of time between re-pricing of the portfolio.

+ References

No definition available.

+ Details

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X

- Definition

Number of investments in debt securities measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in unrealized loss position, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 6
-Subparagraph (b)(3)
-URI http://asc.fasb.org/extlink&oid=123581744&loc=d3e27290-111563

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 50
-Paragraph 4
-Subparagraph (b)(3)
-URI http://asc.fasb.org/extlink&oid=124269663&loc=SL82922888-210455

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X

- Definition

Amount of investment in equity security without readily determinable fair value.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 321
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123583765&loc=SL75117539-209714

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X

- Definition

The cash inflow associated with the sale of securities that had been designated as held-to-maturity. Excludes proceeds from maturities, prepayments and calls by the issuer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=124260329&loc=d3e26853-111562

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3179-108585

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X

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