Note 7 - Fair Value - Schedule of Quantitative Information About Level 3 Fair Value Measurements (Details)	Mar. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Measurement Input, Discount Rate [Member]
Other real estate owned, measurement input	0.1
Fair Value, Nonrecurring [Member]
Other real estate owned	$ 0	$ 88,000
Fair Value, Nonrecurring [Member] \| Commercial Real Estate Portfolio Segment [Member]
Impaired loans	131,000
Fair Value, Nonrecurring [Member] \| Commercial Portfolio Segment [Member]
Impaired loans	40,000
Fair Value, Nonrecurring [Member] \| Fair Value, Inputs, Level 3 [Member]
Other real estate owned		$ 88,000
Fair Value, Nonrecurring [Member] \| Fair Value, Inputs, Level 3 [Member] \| Measurement Input, Comparability Adjustment [Member]
Other real estate owned, measurement input		0.1
Fair Value, Nonrecurring [Member] \| Fair Value, Inputs, Level 3 [Member] \| Commercial Real Estate Portfolio Segment [Member]
Impaired loans	$ 131,000
Fair Value, Nonrecurring [Member] \| Fair Value, Inputs, Level 3 [Member] \| Commercial Real Estate Portfolio Segment [Member] \| Measurement Input, Discount Rate [Member]
Impaired loans, measurement input (Pure)	0.1
Fair Value, Nonrecurring [Member] \| Fair Value, Inputs, Level 3 [Member] \| Commercial Portfolio Segment [Member]
Impaired loans	$ 40,000
Fair Value, Nonrecurring [Member] \| Fair Value, Inputs, Level 3 [Member] \| Commercial Portfolio Segment [Member] \| Measurement Input, Comparability Adjustment [Member] \| Minimum [Member]
Impaired loans, measurement input (Pure)	0.1
Fair Value, Nonrecurring [Member] \| Fair Value, Inputs, Level 3 [Member] \| Commercial Portfolio Segment [Member] \| Measurement Input, Comparability Adjustment [Member] \| Maximum [Member]
Impaired loans, measurement input (Pure)	1
Fair Value, Nonrecurring [Member] \| Fair Value, Inputs, Level 3 [Member] \| Commercial Portfolio Segment [Member] \| Measurement Input, Comparability Adjustment [Member] \| Weighted Average [Member]
Impaired loans, measurement input (Pure)	0.185

The fair value of impaired loans.

No definition available.

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Balance Type:	debit
Period Type:	instant

- 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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Period Type:	instant

- 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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