Note 6 - Loans and the Allowance for Loan Losses - Summary of Information Pertaining to Impaired Loans (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
Jun. 30, 2017	Dec. 31, 2016
Average Recorded Investment	$ 11,904	$ 13,195
Recorded Investment, with no allowance recorded	8,893	10,470
Unpaid Principal Balance, with no allowance recorded	10,591	12,145
Average Recorded Investment, with no allowance recorded	10,117	10,873
Recorded Investment	11,260	12,009
Unpaid Principal Balance	13,074	13,728
Recorded Investment, with an allowance recorded	2,367	1,539
Unpaid Principal Balance, with an allowance recorded	2,483	1,583
Related Allowance	1,032	887
Average Recorded Investment, with an allowance recorded	1,787	2,322
Commercial Real Estate Portfolio Segment [Member] \| Construction and Land [Member]
Average Recorded Investment	137	779
Recorded Investment, with no allowance recorded	44	143
Unpaid Principal Balance, with no allowance recorded	54	152
Average Recorded Investment, with no allowance recorded	77	124
Recorded Investment	133	143
Unpaid Principal Balance	143	152
Recorded Investment, with an allowance recorded	89	0
Unpaid Principal Balance, with an allowance recorded	89	0
Related Allowance	22	0
Average Recorded Investment, with an allowance recorded	60	655
Commercial Real Estate Portfolio Segment [Member] \| Farmland [Member]
Average Recorded Investment	0	0
Recorded Investment, with no allowance recorded	0	0
Unpaid Principal Balance, with no allowance recorded	0	0
Average Recorded Investment, with no allowance recorded	0	0
Recorded Investment	0	0
Unpaid Principal Balance	0	0
Recorded Investment, with an allowance recorded	0	0
Unpaid Principal Balance, with an allowance recorded	0	0
Related Allowance	0	0
Average Recorded Investment, with an allowance recorded	0	0
Commercial Real Estate Portfolio Segment [Member] \| Nonfarm Nonresidential [Member]
Average Recorded Investment	2,431	3,761
Recorded Investment, with no allowance recorded	2,356	705
Unpaid Principal Balance, with no allowance recorded	2,406	729
Average Recorded Investment, with no allowance recorded	2,009	3,730
Recorded Investment	3,049	1,073
Unpaid Principal Balance	3,114	1,097
Recorded Investment, with an allowance recorded	693	368
Unpaid Principal Balance, with an allowance recorded	708	368
Related Allowance	112	98
Average Recorded Investment, with an allowance recorded	422	31
Residential Portfolio Segment [Member] \| Real Estate Residential One- to Four-Family [Member]
Average Recorded Investment	3,117	3,668
Recorded Investment, with no allowance recorded	1,927	2,823
Unpaid Principal Balance, with no allowance recorded	2,290	3,276
Average Recorded Investment, with no allowance recorded	2,309	3,296
Recorded Investment	2,916	3,263
Unpaid Principal Balance	3,359	3,746
Recorded Investment, with an allowance recorded	989	440
Unpaid Principal Balance, with an allowance recorded	1,069	470
Related Allowance	415	252
Average Recorded Investment, with an allowance recorded	808	372
Residential Portfolio Segment [Member] \| Multi-family Residential [Member]
Average Recorded Investment	0	0
Recorded Investment, with no allowance recorded	0	0
Unpaid Principal Balance, with no allowance recorded	0	0
Average Recorded Investment, with no allowance recorded	0	0
Recorded Investment	0	0
Unpaid Principal Balance	0	0
Recorded Investment, with an allowance recorded	0	0
Unpaid Principal Balance, with an allowance recorded	0	0
Related Allowance	0	0
Average Recorded Investment, with an allowance recorded	0	0
Commercial Portfolio Segment [Member]
Average Recorded Investment	6,085	4,932
Recorded Investment, with no allowance recorded	4,331	6,637
Unpaid Principal Balance, with no allowance recorded	5,575	7,826
Average Recorded Investment, with no allowance recorded	5,598	3,680
Recorded Investment	4,927	7,332
Unpaid Principal Balance	6,192	8,535
Recorded Investment, with an allowance recorded	596	695
Unpaid Principal Balance, with an allowance recorded	617	709
Related Allowance	483	501
Average Recorded Investment, with an allowance recorded	487	1,252
Consumer Portfolio Segment [Member]
Average Recorded Investment	134	55
Recorded Investment, with no allowance recorded	235	162
Unpaid Principal Balance, with no allowance recorded	266	162
Average Recorded Investment, with no allowance recorded	124	43
Recorded Investment	235	198
Unpaid Principal Balance	266	198
Recorded Investment, with an allowance recorded	0	36
Unpaid Principal Balance, with an allowance recorded	0	36
Related Allowance	0	36
Average Recorded Investment, with an allowance recorded	$ 10	$ 12

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=84173941&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=84173941&loc=d3e5258-111524

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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 14A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953550-111524

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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 17
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5258-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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-Topic 310
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-Section 50
-Paragraph 15
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5212-111524

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