Note 5 - Loans Receivable (Details) - Impaired Loans (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Impaired loans with a valuation allowance:
Impaired loans with a valuation allowance, unpaid principal balance	$ 4,473	$ 6,988
Impaired loans with a valuation allowance, recorded investment	4,096	6,190
Impaired loans, valuation allowance	1,011	2,162
Impaired loans with a valuation allowance, average recorded investment	4,841	7,709
Impaired loans with a valuation allowance, interest income recognized	21	19
Impaired loans without a valuation allowance:
Impaired loans without a valuation allowance, unpaid principal balance	7,772	7,665
Impaired loans without a valuation allowance, recorded investment	6,240	6,243
Impaired loans without a valuation allowance, average recorded investment	5,961	9,558
Impaired loans without a valuation allowance, interest income recognized	8	2
Impaired loans, unpaid principal balance	12,245	14,653
Impaired loans, recorded investment	10,336	12,433
Impaired loans, valuation allowance	1,011	2,162
Impaired loans, average recorded investment	10,802	17,267
Impaired loans, interest income recognized	29	21
Interest based on original terms	745	873
One-to-Four-Family Residential [Member]
Impaired loans with a valuation allowance:
Impaired loans with a valuation allowance, unpaid principal balance	1,030	1,213
Impaired loans with a valuation allowance, recorded investment	1,204	1,085
Impaired loans, valuation allowance	251	279
Impaired loans with a valuation allowance, average recorded investment	1,141	1,946
Impaired loans with a valuation allowance, interest income recognized	21	19
Impaired loans without a valuation allowance:
Impaired loans without a valuation allowance, unpaid principal balance	4,732	4,430
Impaired loans without a valuation allowance, recorded investment	4,237	3,668
Impaired loans without a valuation allowance, average recorded investment	3,747	4,488
Impaired loans without a valuation allowance, interest income recognized	2	2
Impaired loans, valuation allowance	251	279
Nonfarm Nonresidential [Member]
Impaired loans with a valuation allowance:
Impaired loans with a valuation allowance, unpaid principal balance	2,531	3,287
Impaired loans with a valuation allowance, recorded investment	2,225	3,105
Impaired loans, valuation allowance	580	1,119
Impaired loans with a valuation allowance, average recorded investment	2,517	3,220
Impaired loans without a valuation allowance:
Impaired loans without a valuation allowance, unpaid principal balance	1,619	1,077
Impaired loans without a valuation allowance, recorded investment	888	952
Impaired loans without a valuation allowance, average recorded investment	996	2,362
Impaired loans, valuation allowance	580	1,119
Farmland [Member]
Impaired loans with a valuation allowance:
Impaired loans with a valuation allowance, unpaid principal balance	620	623
Impaired loans with a valuation allowance, recorded investment	484	495
Impaired loans, valuation allowance	123	133
Impaired loans with a valuation allowance, average recorded investment	489	524
Impaired loans without a valuation allowance:
Impaired loans without a valuation allowance, unpaid principal balance	537	554
Impaired loans without a valuation allowance, recorded investment	250	287
Impaired loans without a valuation allowance, average recorded investment	265	393
Impaired loans, valuation allowance	123	133
Construction and Land Development [Member]
Impaired loans with a valuation allowance:
Impaired loans with a valuation allowance, unpaid principal balance	276	1,865
Impaired loans with a valuation allowance, recorded investment	168	1,505
Impaired loans, valuation allowance	45	631
Impaired loans with a valuation allowance, average recorded investment	632	1,176
Impaired loans without a valuation allowance:
Impaired loans without a valuation allowance, unpaid principal balance	507	1,189
Impaired loans without a valuation allowance, recorded investment	540	962
Impaired loans without a valuation allowance, average recorded investment	611	1,517
Impaired loans without a valuation allowance, interest income recognized	6
Impaired loans, valuation allowance	45	631
Commercial Loan [Member]
Impaired loans with a valuation allowance:
Impaired loans with a valuation allowance, average recorded investment	50	153
Impaired loans without a valuation allowance:
Impaired loans without a valuation allowance, unpaid principal balance	362	388
Impaired loans without a valuation allowance, recorded investment	306	350
Impaired loans without a valuation allowance, average recorded investment	327	89
Consumer Loan [Member]
Impaired loans with a valuation allowance:
Impaired loans with a valuation allowance, unpaid principal balance	16
Impaired loans with a valuation allowance, recorded investment	15
Impaired loans, valuation allowance	12
Impaired loans with a valuation allowance, average recorded investment	12	4
Impaired loans without a valuation allowance:
Impaired loans without a valuation allowance, unpaid principal balance	15	27
Impaired loans without a valuation allowance, recorded investment	19	24
Impaired loans without a valuation allowance, average recorded investment	15	17
Impaired loans, valuation allowance	12
Multifamily Residential [Member]
Impaired loans with a valuation allowance:
Impaired loans with a valuation allowance, average recorded investment		686
Impaired loans without a valuation allowance:
Impaired loans without a valuation allowance, average recorded investment		$ 692

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

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 15

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Amount of interest income recognized that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired.

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-Topic 310

-SubTopic 10

-Section 50

-Paragraph 14A

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Amount of allowance for credit losses related to recorded investment.

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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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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).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 40

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=25495931&loc=d3e18794-111554

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