Note 15 - Fair Values of Financial Instruments - Schedule of Quantitative Information About Level 3 Fair Value Measurements (Details) - Fair Value, Nonrecurring [Member]	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Other real estate owned	$ 9,000	$ 88,000
Commercial Portfolio Segment [Member]
Impaired loans	58,000
Commercial Real Estate Portfolio Segment [Member]
Impaired loans	340,000
Fair Value, Inputs, Level 3 [Member]
Other real estate owned	$ 9,000	$ 88,000
Fair Value, Inputs, Level 3 [Member] \| Weighted Average [Member] \| Measurement Input, Comparability Adjustment [Member]
Other real estate owned, measurement input	0.1
Fair Value, Inputs, Level 3 [Member] \| Commercial Portfolio Segment [Member]
Impaired loans	$ 58,000
Fair Value, Inputs, Level 3 [Member] \| Commercial Portfolio Segment [Member] \| Weighted Average [Member] \| Measurement Input, Comparability Adjustment [Member]
Impaired loans, measurement input	0.1
Fair Value, Inputs, Level 3 [Member] \| Commercial Real Estate Portfolio Segment [Member]
Impaired loans	$ 340,000
Fair Value, Inputs, Level 3 [Member] \| Commercial Real Estate Portfolio Segment [Member] \| Measurement Input, Comparability Adjustment [Member]
Impaired loans, measurement input	0.1

The fair value of impaired loans.

No definition available.

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- Definition

Value of input used to measure investment in impaired loans.

+ References

No definition available.

+ Details

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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

+ Details

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- Definition

Value of input used to measure real estate owned by financial institution by financial institution which is not directly related to its business.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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