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Note 8 - Loans and Related Allowance for Loan and Lease Losses - Troubled Debt Restructurings (Details) - Real Estate Mortgage Portfolio Segment [Member] - Residential Loan [Member] $ in Thousands | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2019 USD ($) | Jun. 30, 2018 USD ($) | Jun. 30, 2019 USD ($) | Jun. 30, 2018 USD ($)
Number of contracts |  | 1 | 1 | 2
Pre-modification outstanding recorded investment |  | $ 113 | $ 85 | $ 160
Post-modification outstanding recorded investment | $ 140 | $ 113 |  | $ 160
Extended Maturity [Member] |  |  |  |
Number of contracts |  | 1 |  | 2
Other Restructurings [Member] |  |  |  |
Number of contracts |  |  | 1 |

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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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- Definition Amount, before troubled debt restructuring, of financing receivable to be modified. + 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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- Details
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