Note 1 - Summary of Significant Accounting Policies (Details Textual)	12 Months Ended
Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)
Number of Branches	48
Number of Loan Production Offices	3
Number of Operating Segments	1
Other than Temporary Impairment Losses, Investments	$ 0	$ 0	$ 0
Common Stock Dividend Rate, Percentage	11.00%
Liability for Uncertainty in Income Taxes, Current	$ 0
Minimum [Member]
Property, Plant and Equipment, Useful Life	3 years
Finite-Lived Intangible Asset, Useful Life	12 years
Maximum [Member]
Property, Plant and Equipment, Useful Life	40 years
Finite-Lived Intangible Asset, Useful Life	13 years
One-to-Four-Family Residential [Member] \| Real Estate Portfolio Segment [Member]
Mortgage Loans in Process of Foreclosure, Amount	$ 473,000

The percentage rate used to calculate dividend payments on common stock.

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The number of branch offices operated by the entity.

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Represents the number of loan production offices operated by the company.

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Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The amount by which the fair value of an investment is less than the amortized cost basis or carrying amount of that investment at the balance sheet date and the decline in fair value is deemed to be other than temporary, before considering whether or not such amount is recognized in earnings or other comprehensive income.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3602-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 35
-Paragraph 34
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Amount recognized for uncertainty in income taxes classified as current.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.20)
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- Definition

Recorded investment of consumer mortgage loan receivables secured by residential real estate properties for which formal foreclosure proceedings are in process.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 35
-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL49126937-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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-Glossary Recorded Investment
-URI http://asc.fasb.org/extlink&oid=65880944

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Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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