Note 5 - Loans and Allowance for Loan Losses - Impaired Loans (Details) - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Valuation allowance	$ 1,321		$ 1,096
Loans recorded balance	11,626		11,968
Loans unpaid principal	12,859		13,201
Loans average investment in impaired loans	10,946	$ 18,647
Loans interest income recognized	7	5
Residential Portfolio Segment [Member] \| Real Estate Residential, One To Four Family Units [Member]
Loans without a specific valuation allowance, recorded balance	1,143		1,392
Loans without a specific valuation allowance, unpaid principal	1,143		1,392
Loans with a specific valuation allowance, recorded balance	1,301		1,221
Loans with a specific valuation allowance, unpaid principal	1,301		1,221
Valuation allowance	257		197
Loans recorded balance	2,444		2,613
Loans unpaid principal	2,444		2,613
Loans without a specific valuation allowance, average investment in impaired loans	1,106	1,111
Loans without a specific valuation allowance, interest income recognized	0	1
Loans with a specific valuation allowance, average investment in impaired loans	1,224	2,352
Loans with a specific valuation allowance, interest income recognized	0	0
Loans average investment in impaired loans	2,330	3,463
Loans interest income recognized	0	1
Residential Portfolio Segment [Member] \| Real Estate Residential, Multi Family Units [Member]
Loans without a specific valuation allowance, recorded balance	0		0
Loans without a specific valuation allowance, unpaid principal	0		0
Valuation allowance	0		0
Loans recorded balance	0		0
Loans unpaid principal	0		0
Loans without a specific valuation allowance, average investment in impaired loans	0	5,934
Loans without a specific valuation allowance, interest income recognized	0	0
Loans with a specific valuation allowance, average investment in impaired loans	0	0
Loans with a specific valuation allowance, interest income recognized	0	0
Loans average investment in impaired loans	0	5,934
Loans interest income recognized	0	0
Residential Portfolio Segment [Member] \| Construction Loans [Member]
Loans without a specific valuation allowance, average investment in impaired loans	0	0
Loans without a specific valuation allowance, interest income recognized	0	0
Loans with a specific valuation allowance, average investment in impaired loans	4,188	3,876
Loans with a specific valuation allowance, interest income recognized	0	0
Loans average investment in impaired loans	4,188	3,876
Loans interest income recognized	0	0
Real Estate, Construction [Member]
Loans without a specific valuation allowance, recorded balance	0		0
Loans without a specific valuation allowance, unpaid principal	0		0
Loans with a specific valuation allowance, recorded balance	4,443		4,742
Loans with a specific valuation allowance, unpaid principal	5,676		5,975
Valuation allowance	630		553
Loans recorded balance	4,443		4,742
Loans unpaid principal	5,676		5,975
Commercial Real Estate Portfolio Segment [Member]
Loans without a specific valuation allowance, recorded balance	3,358		3,199
Loans without a specific valuation allowance, unpaid principal	3,358		3,199
Loans with a specific valuation allowance, recorded balance	249		162
Loans with a specific valuation allowance, unpaid principal	249		162
Valuation allowance	96		24
Loans recorded balance	3,607		3,361
Loans unpaid principal	3,607		3,361
Loans without a specific valuation allowance, average investment in impaired loans	3,006	3,440
Loans without a specific valuation allowance, interest income recognized	0	4
Loans with a specific valuation allowance, average investment in impaired loans	236	717
Loans with a specific valuation allowance, interest income recognized	0	0
Loans average investment in impaired loans	3,242	4,157
Loans interest income recognized	0	4
Commercial Portfolio Segment [Member]
Loans without a specific valuation allowance, recorded balance	0		33
Loans without a specific valuation allowance, unpaid principal	0		33
Loans with a specific valuation allowance, recorded balance	864		999
Loans with a specific valuation allowance, unpaid principal	864		999
Valuation allowance	322		301
Loans recorded balance	864		1,032
Loans unpaid principal	864		1,032
Loans without a specific valuation allowance, average investment in impaired loans	9	223
Loans without a specific valuation allowance, interest income recognized	0	0
Loans with a specific valuation allowance, average investment in impaired loans	916	659
Loans with a specific valuation allowance, interest income recognized	0	0
Loans average investment in impaired loans	925	882
Loans interest income recognized	0	0
Consumer and Other Loans [Member]
Loans without a specific valuation allowance, recorded balance	111		70
Loans without a specific valuation allowance, unpaid principal	111		70
Loans with a specific valuation allowance, recorded balance	157		150
Loans with a specific valuation allowance, unpaid principal	157		150
Valuation allowance	16		21
Loans recorded balance	268		220
Loans unpaid principal	268		$ 220
Consumer Portfolio Segment [Member]
Loans without a specific valuation allowance, average investment in impaired loans	105	229
Loans without a specific valuation allowance, interest income recognized	7	0
Loans with a specific valuation allowance, average investment in impaired loans	156	106
Loans with a specific valuation allowance, interest income recognized	0	0
Loans average investment in impaired loans	261	335
Loans interest income recognized	$ 7	$ 0

Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

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 (c)(1)
-URI http://asc.fasb.org/extlink&oid=121611835&loc=d3e5212-111524

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=121611835&loc=d3e5258-111524

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-SubTopic 10
-Section 50
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=121611835&loc=d3e5258-111524

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=121611835&loc=d3e5212-111524

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