Note 8 - Fair Value Disclosure (Details Textual)	3 Months Ended
Mar. 31, 2020 USD ($)	Mar. 31, 2019 USD ($)	Dec. 31, 2019 USD ($)
Impaired Financing Receivable, with Related Allowance, Recorded Investment	$ 3,255,000		$ 4,024,000
Impaired Financing Receivable, Related Allowance	651,000		884,000
Gains (Losses) on Sales of Other Real Estate	4,000	$ 30,000
Commercial Portfolio Segment [Member] \| Real Estate Sector [Member]
Impaired Financing Receivable, with Related Allowance, Recorded Investment	1,619,000		1,646,000
Impaired Financing Receivable, Related Allowance	$ 392,000		274,000
Number of Loans Transferred to Other Real Estate Owned	1	1
Other Real Estate, Ending Balance	$ 18,000	$ 697,000
Gains (Losses) on Sales of Other Real Estate	4,000	33,000
Residential Portfolio Segment [Member] \| Real Estate Sector [Member]
Impaired Financing Receivable, Related Allowance
Other Real Estate, Ending Balance	$ 76,000	46,000
Gains (Losses) on Sales of Other Real Estate		$ (3,000)
Other Real Estate Owned, Number of Properties Sold	2	1

Represents the number of loans transferred to OREO during the reporting period.

No definition available.

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- Definition

Represents the number of OREO properties sold during the period.

+ References

No definition available.

+ Details

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- Definition

The net gain (loss) resulting from sales and other disposals of other real estate owned, increases (decreases) in the valuation allowance for foreclosed real estate, and write-downs of other real estate owned after acquisition or physical possession.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.14(d))
-URI http://asc.fasb.org/extlink&oid=120399700&loc=SL114874048-224260

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- Definition

Amount of allowance for credit losses related to recorded investment.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=121611835&loc=d3e5212-111524

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- Definition

Amount of investment in impaired financing receivables for which there is a related allowance for credit losses.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 14A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953550-111524

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- Definition

Carrying amount of other real estate not separately disclosed, including, but not limited to, real estate investments, real estate loans that qualify as investments in real estate, and premises that are no longer used in operations may also be included in real estate owned. This does not include real estate assets taken in settlement of troubled loans through surrender or foreclosure.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.10(4))
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

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