Note 3 - Loans Receivable and Allowance for Loan Losses - Non-accrual Loans (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Non-accruing loans	$ 1,859	$ 1,821
Residential Portfolio Segment [Member]
Non-accruing loans	1,590	1,590
Commercial Portfolio Segment [Member]
Non-accruing loans	269	231
Substandard [Member]
Non-accruing loans	1,859	1,821
Substandard [Member] \| Residential Portfolio Segment [Member]
Non-accruing loans	1,590	1,590
Substandard [Member] \| Commercial Portfolio Segment [Member]
Non-accruing loans	269	231
Substandard [Member] \| Non-Accrual Loans [Member]
Performing (accruing) loans, past due	1,859	1,821
Performing (accruing) loans, current	0	0
Substandard [Member] \| Non-Accrual Loans [Member] \| Residential Portfolio Segment [Member]
Performing (accruing) loans, past due	1,590	1,590
Performing (accruing) loans, current	0	0
Substandard [Member] \| Non-Accrual Loans [Member] \| Commercial Portfolio Segment [Member]
Performing (accruing) loans, past due	269	231
Performing (accruing) loans, current	0	0
Financing Receivables, 30 to 59 Days Past Due [Member] \| Substandard [Member] \| Non-Accrual Loans [Member]
Performing (accruing) loans, past due	0	0
Financing Receivables, 30 to 59 Days Past Due [Member] \| Substandard [Member] \| Non-Accrual Loans [Member] \| Residential Portfolio Segment [Member]
Performing (accruing) loans, past due	0	0
Financing Receivables, 30 to 59 Days Past Due [Member] \| Substandard [Member] \| Non-Accrual Loans [Member] \| Commercial Portfolio Segment [Member]
Performing (accruing) loans, past due	0	0
Financing Receivables, 60 to 89 Days Past Due [Member] \| Substandard [Member] \| Non-Accrual Loans [Member]
Performing (accruing) loans, past due	0	0
Financing Receivables, 60 to 89 Days Past Due [Member] \| Substandard [Member] \| Non-Accrual Loans [Member] \| Residential Portfolio Segment [Member]
Performing (accruing) loans, past due	0	0
Financing Receivables, 60 to 89 Days Past Due [Member] \| Substandard [Member] \| Non-Accrual Loans [Member] \| Commercial Portfolio Segment [Member]
Performing (accruing) loans, past due	0	0
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] \| Substandard [Member] \| Non-Accrual Loans [Member]
Performing (accruing) loans, past due	1,859	1,821
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] \| Substandard [Member] \| Non-Accrual Loans [Member] \| Residential Portfolio Segment [Member]
Performing (accruing) loans, past due	1,590	1,590
Financing Receivables, Equal to Greater than 90 Days Past Due [Member] \| Substandard [Member] \| Non-Accrual Loans [Member] \| Commercial Portfolio Segment [Member]
Performing (accruing) loans, past due	$ 269	$ 231

Financing receivables that are current.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7A
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953401-111524

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- Definition

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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 7
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5111-111524

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- Definition

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+ References

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