Note 3 - Loans and Allowance for Loan Losses - Recorded Investments in Loans (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Principal loan balance	$ 489,077	$ 506,639
Accrued interest receivable	1,646	1,923
Net deferred loan origination fees and costs	174	317
Recorded investment in loans	490,897	508,879
Individually evaluated for impairment	3,295	3,168
Collectively evaluated for impairment	487,306	505,414
Financial Asset Acquired with Credit Deterioration [Member]
Recorded investment in loans	296	297
Commercial Portfolio Segment [Member]
Principal loan balance	71,916	82,274
Accrued interest receivable	265	378
Net deferred loan origination fees and costs	(991)	(843)
Recorded investment in loans	71,190	81,809
Individually evaluated for impairment	201	211
Collectively evaluated for impairment	70,989	81,598
Commercial Portfolio Segment [Member] \| Financial Asset Acquired with Credit Deterioration [Member]
Recorded investment in loans	0	0
Real Estate Loan [Member] \| Real Estate Mortgage Portfolio Segment [Member]
Principal loan balance	125,129	131,217
Accrued interest receivable	479	513
Net deferred loan origination fees and costs	119	120
Recorded investment in loans	125,727	131,850
Individually evaluated for impairment	1,879	1,728
Collectively evaluated for impairment	123,577	129,851
Real Estate Loan [Member] \| Real Estate Mortgage Portfolio Segment [Member] \| Financial Asset Acquired with Credit Deterioration [Member]
Recorded investment in loans	271	271
Land Loan [Member] \| Real Estate Mortgage Portfolio Segment [Member]
Principal loan balance	17,005	17,328
Accrued interest receivable	78	116
Net deferred loan origination fees and costs	16	17
Recorded investment in loans	17,099	17,461
Individually evaluated for impairment	100	97
Collectively evaluated for impairment	16,999	17,364
Land Loan [Member] \| Real Estate Mortgage Portfolio Segment [Member] \| Financial Asset Acquired with Credit Deterioration [Member]
Recorded investment in loans	0	0
Construction Loans [Member] \| Real Estate Mortgage Portfolio Segment [Member]
Principal loan balance	28,951	24,969
Accrued interest receivable	58	61
Net deferred loan origination fees and costs	(14)	(12)
Recorded investment in loans	28,995	25,018
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	28,995	25,018
Construction Loans [Member] \| Real Estate Mortgage Portfolio Segment [Member] \| Financial Asset Acquired with Credit Deterioration [Member]
Recorded investment in loans	0	0
Commercial Real Estate Loan [Member] \| Real Estate Mortgage Portfolio Segment [Member]
Principal loan balance	133,423	135,114
Accrued interest receivable	416	435
Net deferred loan origination fees and costs	(62)	(65)
Recorded investment in loans	133,777	135,484
Individually evaluated for impairment	760	779
Collectively evaluated for impairment	132,992	134,679
Commercial Real Estate Loan [Member] \| Real Estate Mortgage Portfolio Segment [Member] \| Financial Asset Acquired with Credit Deterioration [Member]
Recorded investment in loans	25	26
Home Equity and Second Mortgage [Member] \| Consumer Portfolio Segment [Member]
Principal loan balance	50,356	52,001
Accrued interest receivable	149	176
Net deferred loan origination fees and costs	1,106	1,100
Recorded investment in loans	51,611	53,277
Individually evaluated for impairment	355	353
Collectively evaluated for impairment	51,256	52,924
Home Equity and Second Mortgage [Member] \| Consumer Portfolio Segment [Member] \| Financial Asset Acquired with Credit Deterioration [Member]
Recorded investment in loans	0	0
Other Consumer Loan [Member] \| Consumer Portfolio Segment [Member]
Principal loan balance	62,297	63,736
Accrued interest receivable	201	244
Net deferred loan origination fees and costs	0	0
Recorded investment in loans	62,498	63,980
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	62,498	63,980
Other Consumer Loan [Member] \| Consumer Portfolio Segment [Member] \| Financial Asset Acquired with Credit Deterioration [Member]
Recorded investment in loans	$ 0	$ 0

Represents loans and leases receivable accrued interest.

No definition available.

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Data Type:	xbrli:monetaryItemType
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- Definition

Represents the loans and leases receivable principal balance.

+ References

No definition available.

+ Details

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- Definition

The balance of financing receivables that were collectively evaluated for impairment.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (h)
-URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953423-111524

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- Definition

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+ References

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- Definition

Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-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

Amount of deferred fees paid by borrowers and unamortized costs incurred to originate loans and leases, unamortized loan commitments and loan syndication fees, and premiums over or discounts from face amounts of loans that are being amortized into income as an adjustment to yield. Excludes amounts for loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6378536&loc=d3e10092-111533

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