Note 5 - Loans Receivable - Impaired Loans (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Unpaid principal balance - with allowance	$ 2,114	$ 5,147	$ 4,473
Recorded investment - with allowance	2,022	4,546	4,096
Valuation allowance	567	1,061	1,011
Average recorded investment - with allowance	3,933	4,589	4,841
Interest income recognzied - with allowance	7	7	21
Unpaid principal balance - with no allowance	24,757	18,202	7,772
Recorded investment - with no allowance	20,158	15,078	6,240
Average recorded investment - with no allowance	16,034	9,056	5,961
Interest income recognzied - with no allowance	6	7	8
Unpaid principal balance	26,871	23,349	12,245
Recorded investment	22,180	19,624	10,336
Average recorded investment	19,967	13,645	10,802
Interest income recognzied	13	14	29
Interest based on original terms	1,360	1,179	745
Real Estate Portfolio Segment [Member] \| One-to-Four-Family Residential [Member]
Unpaid principal balance - with allowance	244	430	1,030
Recorded investment - with allowance	229	312	1,204
Valuation allowance	74	83	251
Average recorded investment - with allowance	332	833	1,141
Interest income recognzied - with allowance	7	7	21
Unpaid principal balance - with no allowance	8,704	7,605	4,732
Recorded investment - with no allowance	6,677	6,348	4,237
Average recorded investment - with no allowance	7,074	4,902	3,747
Interest income recognzied - with no allowance	0	1	2
Real Estate Portfolio Segment [Member] \| Nonfarm Nonresidential [Member]
Unpaid principal balance - with allowance	0	2,728	2,531
Recorded investment - with allowance	0	2,395	2,225
Valuation allowance	0	522	580
Average recorded investment - with allowance	903	2,651	2,517
Interest income recognzied - with allowance	0	0	0
Unpaid principal balance - with no allowance	11,022	5,352	1,619
Recorded investment - with no allowance	9,421	4,243	888
Average recorded investment - with no allowance	5,656	1,759	996
Interest income recognzied - with no allowance	0	0	0
Real Estate Portfolio Segment [Member] \| Farmland [Member]
Unpaid principal balance - with allowance	0	616	620
Recorded investment - with allowance	0	473	484
Valuation allowance	0	112	123
Average recorded investment - with allowance	95	479	489
Interest income recognzied - with allowance	0	0	0
Unpaid principal balance - with no allowance	1,226	796	537
Recorded investment - with no allowance	783	499	250
Average recorded investment - with no allowance	740	303	265
Interest income recognzied - with no allowance	0	0	0
Real Estate Portfolio Segment [Member] \| Construction Loans [Member]
Unpaid principal balance - with allowance	0	215	276
Recorded investment - with allowance	0	211	168
Valuation allowance	0	89	45
Average recorded investment - with allowance	75	152	632
Interest income recognzied - with allowance	0	0	0
Unpaid principal balance - with no allowance	728	686	507
Recorded investment - with no allowance	539	490	540
Average recorded investment - with no allowance	593	535	611
Interest income recognzied - with no allowance	6	6	6
Real Estate Portfolio Segment [Member] \| Multifamily Residential [Member]
Unpaid principal balance - with no allowance	0	282
Recorded investment - with no allowance	0	230
Average recorded investment - with no allowance	107	50
Interest income recognzied - with no allowance	0	0
Commercial Portfolio Segment [Member]
Unpaid principal balance - with allowance	1,865	1,153	0
Recorded investment - with allowance	1,788	1,150	0
Valuation allowance	488	250	0
Average recorded investment - with allowance	2,523	461	50
Interest income recognzied - with allowance	0	0	0
Unpaid principal balance - with no allowance	2,893	3,293	362
Recorded investment - with no allowance	2,570	3,085	306
Average recorded investment - with no allowance	1,664	1,399	327
Interest income recognzied - with no allowance	0	0	0
Consumer Portfolio Segment [Member]
Unpaid principal balance - with allowance	5	5	16
Recorded investment - with allowance	5	5	15
Valuation allowance	5	5	12
Average recorded investment - with allowance	5	13	12
Interest income recognzied - with allowance	0	0	0
Unpaid principal balance - with no allowance	184	188	15
Recorded investment - with no allowance	168	183	19
Average recorded investment - with no allowance	200	108	15
Interest income recognzied - with no allowance	$ 0	$ 0	$ 0

Average 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 15
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5212-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5258-111524

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

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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-Section 50
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-URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5258-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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