Note 5 - Loans Held for Sale (Details Textual)	9 Months Ended
Sep. 30, 2020 USD ($)	Sep. 30, 2019 USD ($)	Dec. 31, 2019 USD ($)
Loans Serviced By Entity But Owned By a Third Party	$ 18,600,000		$ 13,600,000
Servicing Asset, Total	301,000
Servicing Asset at Fair Value, Amount, Ending Balance	362,000
SBA CARES Act Paycheck Protection Program [Member]
Financing Receivable, Held-for-Sale, Not Part of Disposal Group, after Valuation Allowance, Ending Balance	1,800,000		15,300,000
Transfer of Loans Held-for-sale to Portfolio Loans	$ 9,542,000
Commercial Portfolio Segment [Member]
Number of Loans Held-for-Sale	1
Financing Receivable, Held-for-Sale, Not Part of Disposal Group, after Valuation Allowance, Ending Balance	$ 5,000,000
Commercial Portfolio Segment [Member] \| SBA CARES Act Paycheck Protection Program [Member]
Financing Receivable, Held-for-Sale, Not Part of Disposal Group, after Valuation Allowance, Ending Balance	851,000		10,200,000
Commercial Real Estate Portfolio Segment [Member] \| SBA CARES Act Paycheck Protection Program [Member]
Financing Receivable, Held-for-Sale, Not Part of Disposal Group, after Valuation Allowance, Ending Balance	$ 950,000		$ 5,100,000

Represents the amount of loans serviced by the reporting entity but owned by a third party, as of a specified date.

No definition available.

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- Definition

Represents number of loans held for sale.

+ References

No definition available.

+ Details

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- Definition

Amount, after valuation allowance, of financing receivable held for sale and not part of disposal group. Excludes loan covered under loss sharing agreement and loan classified as investment in debt security.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=121593590&loc=d3e4428-111522

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- Definition

Aggregate amount of servicing assets that are subsequently measured at fair value and servicing assets that are subsequently measured using the amortization method.

+ References

+ Details

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- Definition

Fair value of an asset representing net future revenue from contractually specified servicing fees, late charges, and other ancillary revenues, in excess of future costs related to servicing arrangements.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 50
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- Definition

Value of loans held-for-sale transferred to loans held in the entity's portfolio in noncash transactions.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
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