Note 3 - Securities (Details Textual)	6 Months Ended	12 Months Ended
Jun. 30, 2020 USD ($)	Jun. 30, 2019 USD ($)	Dec. 31, 2019 USD ($)
Equity Securities, FV-NI	$ 0	$ 125,000
Equity Securities, FV-NI, Unrealized Gain	(0)	330,000
Proceeds from the Sale of Equity Securities	$ 0	$ 317,000
Par Value of Restricted Stock Out of Outstanding Capital Required by FRB	3.00%
Par Value of Federal Reserve Banks Restricted Stock Outstanding Capital Subject to Call	3.00%
Par Value of Restricted Stock Out of Outstanding Capital Required by FHLB	4.25%
Other than Temporary Impairment Losses, Investments, Total	$ 0		$ 0
US Government-sponsored Enterprises Debt Securities [Member]
Debt Securities, Available-for-sale, Unrealized Loss Position, Number of Positions	16
Other-than-temporary Impairment Loss, Debt Securities, Available-for-sale, Total	$ 0
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Number of Positions	12
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Debt Securities, Available-for-sale, Unrealized Loss Position, Number of Positions	2
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	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	2
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	5
Other-than-temporary Impairment Loss, Debt Securities, Available-for-sale, Total	$ 0

The percentage of par value of federal reserve restricted stock outstanding capital subject to call.

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- Definition

The percentage of par value of restricted stock out of outstanding borrowings required by Federal Home Loan Bank.

+ References

No definition available.

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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

Amount of cash inflow from sale of equity securities.

+ 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

Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 45
-Paragraph 1A
-URI http://asc.fasb.org/extlink&oid=99377092&loc=SL75136599-209740

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- Definition

Amount of unrealized gain on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 321
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=120269885&loc=SL75117546-209714

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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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