Note 4 - Loans and Allowance for Loan Losses - Impaired Loans (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016
Loans average investment in impaired loans	$ 8,741	$ 12,181	$ 8,923	$ 12,945
Loans recorded balance	8,579		8,579		$ 8,699
Loans unpaid principal	10,313		10,313		10,384
Valuation allowance	774		774		602
Loans interest income recognized		1		1
Residential Portfolio Segment [Member] \| One To Four Family Units [Member]
Loans average investment in impaired loans	1,869	2,216	1,899	2,244
Loans recorded balance	1,848		1,848		2,060
Loans unpaid principal	1,848		1,848		2,060
Loans without a specific valuation allowance, recorded balance	1,802		1,802		2,006
Loans without a specific valuation allowance, unpaid principal	1,802		1,802		2,006
Loans with a specific valuation allowance, recorded balance	46		46		54
Loans with a specific valuation allowance, unpaid principal	46		46		54
Valuation allowance	65		65		14
Loans without a specific valuation allowance, average investment in impaired loans	1,823	2,207	1,856	2,223
Loans interest income recognized
Loans with a specific valuation allowance, average investment in impaired loans	46	9	43	21
Residential Portfolio Segment [Member] \| Multi Family Units [Member]
Loans average investment in impaired loans
Loans recorded balance
Loans unpaid principal
Loans without a specific valuation allowance, recorded balance
Loans without a specific valuation allowance, unpaid principal
Valuation allowance
Loans without a specific valuation allowance, average investment in impaired loans
Loans interest income recognized
Loans with a specific valuation allowance, average investment in impaired loans
Residential Portfolio Segment [Member] \| Construction Loans [Member]
Loans average investment in impaired loans	5,363	7,928	5,384	8,001
Loans recorded balance	5,364		5,364		5,447
Loans unpaid principal	6,597		6,597		6,680
Loans without a specific valuation allowance, recorded balance	2,967		2,967		3,017
Loans without a specific valuation allowance, unpaid principal	2,967		2,967		3,017
Loans with a specific valuation allowance, recorded balance	2,397		2,397		2,430
Loans with a specific valuation allowance, unpaid principal	3,630		3,630		3,663
Valuation allowance	277		277		302
Loans without a specific valuation allowance, average investment in impaired loans	2,966	5,662	2,978	5,693
Loans interest income recognized
Loans with a specific valuation allowance, average investment in impaired loans	2,397	2,266	2,406	2,308
Commercial Real Estate Portfolio Segment [Member]
Loans average investment in impaired loans	398	525	460	863
Loans recorded balance	328		328		161
Loans unpaid principal	328		328		161
Loans without a specific valuation allowance, recorded balance	328		328		161
Loans without a specific valuation allowance, unpaid principal	328		328		161
Loans with a specific valuation allowance, recorded balance
Loans with a specific valuation allowance, unpaid principal
Valuation allowance	93		93
Loans without a specific valuation allowance, average investment in impaired loans	398	525	460	863
Loans interest income recognized
Loans with a specific valuation allowance, average investment in impaired loans
Commercial Portfolio Segment [Member]
Loans average investment in impaired loans	1,027	1,264	1,090	1,657
Loans recorded balance	975		975		925
Loans unpaid principal	1,476		1,476		1,377
Loans without a specific valuation allowance, recorded balance	540		540		622
Loans without a specific valuation allowance, unpaid principal	540		540		622
Loans with a specific valuation allowance, recorded balance	435		435		303
Loans with a specific valuation allowance, unpaid principal	936		936		755
Valuation allowance	327		327		241
Loans without a specific valuation allowance, average investment in impaired loans	564	872	583	1,112
Loans interest income recognized
Loans with a specific valuation allowance, average investment in impaired loans	463	392	507	545
Consumer Portfolio Segment [Member]
Loans average investment in impaired loans	84	248	90	180
Loans without a specific valuation allowance, average investment in impaired loans	13	128	11	78
Loans interest income recognized		1		1
Loans with a specific valuation allowance, average investment in impaired loans	71	$ 120	79	$ 102
Consumer Portfolio Segment [Member] \| Other Loans [Member]
Loans recorded balance	64		64		106
Loans unpaid principal	64		64		106
Loans without a specific valuation allowance, recorded balance	6		6		3
Loans without a specific valuation allowance, unpaid principal	6		6		3
Loans with a specific valuation allowance, recorded balance	58		58		103
Loans with a specific valuation allowance, unpaid principal	58		58		103
Valuation allowance	$ 12		$ 12		$ 45

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://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5212-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5258-111524

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 14A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953550-111524

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5258-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5212-111524

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