Note 4 - Loans and Allowance for Loan Losses - Loans Modified in a Troubled Debt Restructuring (Details) $ in Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2017 USD ($)	Dec. 31, 2016 USD ($)
Number of loans	7	8
Pre- modification outstanding principal balance	$ 594	$ 2,447
Post- modification principal balance	$ 393	$ 1,664
Real Estate [Member] \| Construction, Land Development and Other Land Loans [Member]
Number of loans	1	2
Pre- modification outstanding principal balance	$ 107	$ 1,960
Post- modification principal balance	$ 84	$ 1,286
Real Estate [Member] \| Secured by 1-4 Family Residential Properties [Member]
Number of loans	3	3
Pre- modification outstanding principal balance	$ 318	$ 318
Post- modification principal balance	$ 188	$ 249
Real Estate [Member] \| Secured by Non-farm, Non-residential Properties [Member]
Number of loans	1	1
Pre- modification outstanding principal balance	$ 53	$ 53
Post- modification principal balance	$ 38	$ 41
Commercial and Industrial Loans [Member]
Number of loans	2	2
Pre- modification outstanding principal balance	$ 116	$ 116
Post- modification principal balance	$ 83	$ 88

Number of financing receivables that have been modified by troubled debt restructurings.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953676-111524

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