Note 3 - Loans Receivable and Allowance for Loan Losses (Details)	3 Months Ended	12 Months Ended
Mar. 31, 2016 USD ($)	Mar. 31, 2015 USD ($)	Dec. 31, 2015 USD ($)
Note 3 - Loans Receivable and Allowance for Loan Losses (Details) [Line Items]
Loans and Leases Receivable, Gross	$ 485,183,000		$ 484,369,000
Maximum Period of Credit Extension of Construction Loans	18 months
Period for Charged Off of Open-End Credits			180 days
Period for Charged Off of Close-End Credits	120 days
Impaired Financing Receivable, Unpaid Principal Balance	$ 18,559,000		$ 14,837,000
Loans and Leases Receivable, Impaired, Interest Lost on Nonaccrual Loans	$ 139,000	$ 4,000
Maximum Period for Charged Off of Consumer Installment Loans	90 days
Number of Non-Accruing Loans	5
Financing Receivable, Recorded Investment, Nonaccrual Status	$ 5,409,000		1,593,000
Impaired Financing Receivable, Related Allowance	739,000		3,000
Impaired loans	$ 16,581,000		$ 12,851,000
Financing Receivable, Modifications, Number of Contracts	0		0
Loans and Leases Receivable, Impaired, Commitment to Lend	$ 0		$ 0
Non-Accrual Loans [Member]
Note 3 - Loans Receivable and Allowance for Loan Losses (Details) [Line Items]
Impaired Financing Receivable, Unpaid Principal Balance	5,400,000		1,600,000
Residential Portfolio Segment [Member]
Note 3 - Loans Receivable and Allowance for Loan Losses (Details) [Line Items]
Loans and Leases Receivable, Gross	108,111,000		110,837,000
Impaired Financing Receivable, Unpaid Principal Balance	5,538,000		5,559,000
Financing Receivable, Recorded Investment, Nonaccrual Status	1,590,000		1,590,000
Impaired Financing Receivable, Related Allowance	0		0
Impaired loans	4,535,000		4,556,000
Residential Portfolio Segment [Member] \| Reclassified from Commercial and Industrial Portfolio Segment [Member]
Note 3 - Loans Receivable and Allowance for Loan Losses (Details) [Line Items]
Loans and Leases Receivable, Gross			28,200,000
Commercial Real Estate Portfolio Segment [Member]
Note 3 - Loans Receivable and Allowance for Loan Losses (Details) [Line Items]
Loans and Leases Receivable, Gross	$ 243,823,000		245,828,000
Maximum Percentage of Credit Extension Based on Market Value of Collateral	75.00%
Impaired Financing Receivable, Unpaid Principal Balance	$ 9,027,000		8,259,000
Financing Receivable, Recorded Investment, Nonaccrual Status	840,000		0
Impaired Financing Receivable, Related Allowance	0		0
Impaired loans	$ 8,521,000		7,745,000
Multi-family Real Estate [Member]
Note 3 - Loans Receivable and Allowance for Loan Losses (Details) [Line Items]
Maximum Percentage of Credit Extension Based on Market Value of Collateral	80.00%
Construction Portfolio Segment [Member]
Note 3 - Loans Receivable and Allowance for Loan Losses (Details) [Line Items]
Loans and Leases Receivable, Gross	$ 21,748,000		15,551,000
Percentage of Maximum Loan to Value	75.00%
Impaired Financing Receivable, Unpaid Principal Balance	$ 287,000		287,000
Financing Receivable, Recorded Investment, Nonaccrual Status			0
Impaired Financing Receivable, Related Allowance	0		0
Impaired loans	$ 0		$ 0

Maximum percentage of credit extension based on market value of collateral.

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Maximum period for charged off of consumer installment loans.

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Maximum period of credit extension of construction loans.

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The number of loans on non-accruing status.

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Percentage of maximum loan to value.

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Period for charged off of close end credits.

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Period for charged off of open end credits

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- Definition

Number of financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953676-111524

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Recorded investment in financing receivables that are on nonaccrual status as of the balance sheet date.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=65880944

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-URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5111-111524

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

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-Name Accounting Standards Codification
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Amount of allowance for credit losses related to recorded investment.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Recorded Investment
-URI http://asc.fasb.org/extlink&oid=65880944

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Amount of unpaid principal balance of impaired financing receivables with related allowance for credit losses and without related allowance for credit losses.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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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.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=65884687&loc=d3e4428-111522

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Reflects the unfunded portion of contractual agreements to lend funds to borrowers for loans whose terms have been modified by troubled debt restructuring.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Reflects the amount of additional interest income that would have been recorded if impaired or nonperforming loans were instead current, in compliance with their original terms, and outstanding throughout the reporting period or since origination (if held for part of the period).

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