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Note 8 - Loans and Related Allowance for Loan and Lease Losses - Troubled Debt Restructurings (Details) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2021 | Sep. 30, 2020 USD ($) | Sep. 30, 2021 | Sep. 30, 2020 USD ($)
Number of contracts | 0 |  | 0 |
Residential Portfolio Segment [Member] |  |  |  |
Number of contracts |  | 1 |  | 3
Pre-modification outstanding recorded investment |  | $ 115 |  | $ 156
Post-modification outstanding recorded investment |  | $ 115 |  | $ 156
Commercial And Industrial [Member] |  |  |  |
Number of contracts |  | 1 |  | 3
Pre-modification outstanding recorded investment |  | $ 2 |  | $ 120
Post-modification outstanding recorded investment |  | $ 2 |  | $ 119
Extended Maturity [Member] | Residential Portfolio Segment [Member] |  |  |  |
Number of contracts |  | 1 |  | 3
Extended Maturity [Member] | Commercial And Industrial [Member] |  |  |  |
Number of contracts |  | 1 |  | 3
Other Restructurings [Member] | Residential Portfolio Segment [Member] |  |  |  |
Number of contracts |  | 0 |  | 0
Other Restructurings [Member] | Commercial And Industrial [Member] |  |  |  |
Number of contracts |  | 0 |  | 0

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=123577603&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=123577603&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=123577603&loc=SL6953676-111524 + Details
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