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Note 8 - Loans and Related Allowance for Loan and Lease Losses - Troubled Debt Restructurings (Details) $ in Thousands | 3 Months Ended
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Mar. 31, 2020 USD ($) | Mar. 31, 2019
Number of contracts |  | 0
Residential Portfolio Segment [Member] |  |
Number of contracts | 2 |
Pre-modification outstanding recorded investment | $ 42 |
Post-modification outstanding recorded investment | $ 42 |
Commercial And Industrial [Member] |  |
Number of contracts | 1 |
Pre-modification outstanding recorded investment | $ 95 |
Post-modification outstanding recorded investment | $ 95 |
Extended Maturity [Member] | Residential Portfolio Segment [Member] |  |
Number of contracts | 2 |
Extended Maturity [Member] | Commercial And Industrial [Member] |  |
Number of contracts | 1 |
Other Restructurings [Member] | Residential Portfolio Segment [Member] |  |
Number of contracts |  |
Other Restructurings [Member] | Commercial And Industrial [Member] |  |
Number of contracts |  |

X
- 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=121611835&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=121611835&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=121611835&loc=SL6953676-111524 + Details
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- Details
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