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Note 5 - Loans and Related Allowance for Loan and Lease Losses - Troubled Debt Restructurings (Details) $ in Thousands | 12 Months Ended
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Dec. 31, 2020 USD ($) | Dec. 31, 2019 USD ($)
Pre-modification outstanding recorded investment | $ 139 | $ 782
Post-modification outstanding recorded investment | $ 138 | $ 844
Commercial And Industrial [Member] |  |
Number of contracts | 2 | 3
Pre-modification outstanding recorded investment | $ 25 | $ 488
Post-modification outstanding recorded investment | $ 24 | $ 490
Residential Portfolio Segment [Member] |  |
Number of contracts | 1 | 2
Pre-modification outstanding recorded investment | $ 114 | $ 123
Post-modification outstanding recorded investment | $ 114 | $ 178
Home Equity Lines of Credit [Member] |  |
Number of contracts |  | 4
Pre-modification outstanding recorded investment |  | $ 171
Post-modification outstanding recorded investment |  | $ 176
Extended Maturity [Member] | Commercial And Industrial [Member] |  |
Number of contracts | 2 | 3
Extended Maturity [Member] | Residential Portfolio Segment [Member] |  |
Number of contracts | 1 | 0
Extended Maturity [Member] | Home Equity Lines of Credit [Member] |  |
Number of contracts |  | 4
Other Restructurings [Member] | Commercial And Industrial [Member] |  |
Number of contracts | 0 | 0
Other Restructurings [Member] | Residential Portfolio Segment [Member] |  |
Number of contracts | 0 | 2
Other Restructurings [Member] | Home Equity Lines of Credit [Member] |  |
Number of contracts |  | 0

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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=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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