Note 5 - Impaired Loans (Details) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Real Estate Portfolio Segment [Member] \| One-to-Four-Family Residential [Member]
Impaired loans with a valuation allowance, unpaid principal balance	$ 1,025	$ 430
Impaired loans with a valuation allowance, recorded investment	651	312
Impaired loans, valuation allowance	109	83
Impaired loans without a valuation allowance, unpaid principal balance	9,614	7,605
Impaired loans without a valuation allowance, recorded investment	7,990	6,348
Real Estate Portfolio Segment [Member] \| Nonfarm Nonresidential [Member]
Impaired loans with a valuation allowance, unpaid principal balance	900	2,728
Impaired loans with a valuation allowance, recorded investment	723	2,395
Impaired loans, valuation allowance	148	522
Impaired loans without a valuation allowance, unpaid principal balance	5,813	5,352
Impaired loans without a valuation allowance, recorded investment	$ 4,934	4,243
Real Estate Portfolio Segment [Member] \| Farmland [Member]
Impaired loans with a valuation allowance, unpaid principal balance		616
Impaired loans with a valuation allowance, recorded investment		473
Impaired loans, valuation allowance		112
Impaired loans without a valuation allowance, unpaid principal balance	$ 1,255	796
Impaired loans without a valuation allowance, recorded investment	817	499
Real Estate Portfolio Segment [Member] \| Construction Loans [Member]
Impaired loans with a valuation allowance, unpaid principal balance	172	215
Impaired loans with a valuation allowance, recorded investment	166	211
Impaired loans, valuation allowance	84	89
Impaired loans without a valuation allowance, unpaid principal balance	890	686
Impaired loans without a valuation allowance, recorded investment	783	490
Commercial Portfolio Segment [Member]
Impaired loans with a valuation allowance, unpaid principal balance	3,269	1,153
Impaired loans with a valuation allowance, recorded investment	3,261	1,150
Impaired loans, valuation allowance	457	250
Impaired loans without a valuation allowance, unpaid principal balance	1,126	3,293
Impaired loans without a valuation allowance, recorded investment	947	3,085
Consumer Portfolio Segment [Member]
Impaired loans with a valuation allowance, unpaid principal balance	5	5
Impaired loans with a valuation allowance, recorded investment	5	5
Impaired loans, valuation allowance	5	5
Impaired loans without a valuation allowance, unpaid principal balance	266	188
Impaired loans without a valuation allowance, recorded investment	255	183
Multifamily Residential [Member]
Impaired loans without a valuation allowance, unpaid principal balance	161	282
Impaired loans without a valuation allowance, recorded investment	157	230
Impaired loans with a valuation allowance, unpaid principal balance	5,371	5,147
Impaired loans with a valuation allowance, recorded investment	4,806	4,546
Impaired loans, valuation allowance	803	1,061
Impaired loans without a valuation allowance, unpaid principal balance	19,125	18,202
Impaired loans without a valuation allowance, recorded investment	15,883	15,078
Total impaired loans	24,496	23,349
Total impaired loans	$ 20,689	$ 19,624

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 14A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953550-111524

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+ References

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

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5212-111524

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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 15
-Subparagraph (a)(4)
-URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5212-111524

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