Note 6 - Loans and Allowance for Loan Losses - Average Net Investment Impaired Loans and Interest Income Recognized and Received on Impaired Loans (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2016	Dec. 31, 2015
Real Estate [Member] \| Construction, Land Development and Other Land Loans [Member]
Average Recorded Investment	$ 1,388	$ 1,493
Interest Income Recognized	32	44
Interest Income Received	32	46
Real Estate [Member] \| Secured by 1-4 Family Residential Properties [Member]
Average Recorded Investment	245	139
Interest Income Recognized	10	14
Interest Income Received	11	14
Real Estate [Member] \| Secured by Multi-family Residential Properties [Member]
Average Recorded Investment		1,892
Interest Income Recognized
Interest Income Received
Real Estate [Member] \| Secured by Non-farm, Non-residential Properties [Member]
Average Recorded Investment	559	3,329
Interest Income Recognized	25	35
Interest Income Received	24	36
Real Estate [Member]
Average Recorded Investment		264
Interest Income Recognized		26
Interest Income Received		26
Commercial and Industrial Loans [Member]
Average Recorded Investment
Interest Income Recognized
Interest Income Received
Average Recorded Investment	2,192	7,117
Interest Income Recognized	67	119
Interest Income Received	$ 67	$ 122

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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- Definition

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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- Definition

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