Note 3 - Loans and Allowance for Loan Losses (Details Textual)	12 Months Ended
Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)
Financing Receivable Modification, Number of Contracts Paid in Full	3		2
Financing Receivable, Modifications, Number of Contracts	15	1	0
Impaired Financing Receivable, Guaranteed by Small Business Administration	$ 1,500,000	$ 100,000
Performing Financial Instruments [Member]
Financing Receivable, Re-modifications, Number of Contracts		1
Financing Receivable, Re-modifications, Recorded Investment, Additional Advancement		$ 28,000
Financing Receivable, Modifications, Number of Contracts	33	24
Financing Receivable, Modifications, Recorded Investment	$ 17,435,000	$ 9,509,000
Nonperforming Financial Instruments [Member]
Financing Receivable, Modifications, Number of Contracts	0	1	3
Financing Receivable, Modifications, Recorded Investment		$ 400,000	$ 2,700,000
Multi-family Residential Property and Commercial Real Estate and Commerical Business and Other Loans [Member]
Loan Origination, Underwriting Requirements, Minimum Debt Service Coverage	125.00%
Loan Origination, Value, Maximum Percentage	75.00%
Multi-family Residential Property and Commercial Real Estate and Commerical Business and Other Loans [Member] \| Gross Loans [Member] \| Credit Concentration Risk [Member]
Concentration Risk, Percentage	83.50%

Represents the number of contracts paid in full.

No definition available.

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

Advancement of an additional amount of investment in financing receivables re-modified by troubled debt restructurings.

+ References

No definition available.

+ Details

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- Definition

The portion of recorded impaired financing receivable that has been guaranteed by the Small Business Administration.

+ References

No definition available.

+ Details

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- Definition

The minimum debt service coverage percentage required to meet the company's underwriting requirements for loan origination.

+ References

No definition available.

+ Details

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- Definition

The maximum percentage of appraised value or purchase price of property of which the company will originate loans.

+ References

No definition available.

+ Details

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 18
-URI http://asc.fasb.org/extlink&oid=64851502&loc=d3e6351-108592

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=73719730&loc=d3e13531-108611

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=64851502&loc=d3e6404-108592

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 21
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=73719730&loc=d3e13537-108611

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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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- Definition

The amount of the outstanding recorded investment related to 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 40
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=25495931&loc=d3e18845-111554

Reference 2: 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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