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Note 5 - Loans and Allowance for Loan Losses - Loans Modified in a Troubled Debt Restructuring (Details) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2019 USD ($) | Dec. 31, 2018 USD ($)
Number of loans | 6 | 7
Pre- modification outstanding principal balance | $ 541 | $ 594
Post- modification principal balance | $ 214 | $ 297
Real Estate [Member] | Construction, Land Development and Other Land Loans [Member] |  |
Number of loans | 1 | 1
Pre- modification outstanding principal balance | $ 107 | $ 107
Post- modification principal balance | $ 71 | $ 73
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 | $ 74 | $ 118
Real Estate [Member] | Secured by Non-farm, Non-residential Properties [Member] |  |
Number of loans |  | 1
Pre- modification outstanding principal balance |  | $ 53
Post- modification principal balance |  | $ 34
Commercial and Industrial Loans [Member] |  |
Number of loans | 2 | 2
Pre- modification outstanding principal balance | $ 116 | $ 116
Post- modification principal balance | $ 69 | $ 72

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- Definition Number of financing receivables that have been modified by troubled debt restructurings. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 33 -URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953676-111524 + Details
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- Definition Amount, after troubled debt restructuring, of modified financing receivable. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 33 -URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953676-111524 + Details
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