Note 2 - Securities (Details Textual) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2021	Dec. 31, 2020
Par Value of Restricted Stock Out of Outstanding Borrowings Required by FHLB	3.00%
Par Value of Restricted Stock Out of Outstanding Capital Required by FRB	3.00%
Percentage of Par Value of Federal Reserve Banks Restricted Stock Outstanding Capital Subject to Call	3.75%
Other than Temporary Impairment Losses, Investments, Total	$ 0	$ 0
Investment in Federal Home Loan Bank Stock [Member]
Other than Temporary Impairment Losses, Investments, Total	$ 0
US Treasury Securities [Member]
Debt Securities, Available-for-sale, Unrealized Loss Position, Number of Positions	5
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Positions	0
Other-than-temporary Impairment Loss, Debt Securities, Available-for-sale, Total	$ 0
US Government-sponsored Enterprises Debt Securities [Member]
Debt Securities, Available-for-sale, Unrealized Loss Position, Number of Positions	24
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Positions	10
Other-than-temporary Impairment Loss, Debt Securities, Available-for-sale, Total	$ 0
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Debt Securities, Available-for-sale, Unrealized Loss Position, Number of Positions	13
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Positions	0
Other-than-temporary Impairment Loss, Debt Securities, Available-for-sale, Total	$ 0
Collateralized Mortgage Backed Securities [Member]
Debt Securities, Available-for-sale, Unrealized Loss Position, Number of Positions	9
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Positions	1
Other-than-temporary Impairment Loss, Debt Securities, Available-for-sale, Total	$ 0
US States and Political Subdivisions Debt Securities [Member]
Debt Securities, Available-for-sale, Unrealized Loss Position, Number of Positions	28
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Positions	0
Other-than-temporary Impairment Loss, Debt Securities, Available-for-sale, Total	$ 0
Corporate Debt Securities [Member]
Debt Securities, Available-for-sale, Unrealized Loss Position, Number of Positions	1
Other-than-temporary Impairment Loss, Debt Securities, Available-for-sale, Total	$ 0

Represents the percentage of par value of restricted stock out of outstanding capital required by Federal Reserve Bank.

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- Definition

The percentage of par value of restricted stock out of outstanding capital required by Federal Reserve Bank.

+ References

No definition available.

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- Definition

Percentage of Par Value of Federal Reserve Banks Restricted Stock Outstanding Capital Subject to Call

+ References

No definition available.

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- 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 continuous unrealized loss position for 12 months or longer, without an allowance for credit loss. Includes beneficial interest in securitized financial asset.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 50
-Paragraph 4
-Subparagraph (b)(3)
-URI http://asc.fasb.org/extlink&oid=121582814&loc=SL82922888-210455

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- 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=121645371&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=121582814&loc=SL82922888-210455

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- Definition

The amount by which the fair value of an investment is less than the amortized cost basis or carrying amount of that investment at the balance sheet date and the decline in fair value is deemed to be other than temporary, before considering whether or not such amount is recognized in earnings or other comprehensive income.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 8A
-URI http://asc.fasb.org/extlink&oid=121553693&loc=SL6284422-111562

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Amount of other-than-temporary impairment (OTTI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), recognized in earnings and other comprehensive loss (OCI).

+ References

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