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Note 8 - Loans and Related Allowance for Loan and Lease Losses - Allowance for Loan Losses (Details) - USD ($) $ in Thousands | Sep. 30, 2020 | Jun. 30, 2020 | Dec. 31, 2019 | Sep. 30, 2019 | Jun. 30, 2019 | Dec. 31, 2018
--- | --- | --- | --- | --- | --- | ---
Individually evaluated for impairment | $ 515 |  | $ 660 |  |  |
Collectively evaluated for impairment | 10,844 |  | 6,108 |  |  |
Less: allowance for loan and lease losses | 11,359 | $ 10,210 | 6,768 | $ 7,001 | $ 7,304 | $ 7,428
Commercial Real Estate Portfolio Segment [Member] | Owner Occupied Loan [Member] |  |  |  |  |  |
Individually evaluated for impairment | 10 |  | 45 |  |  |
Collectively evaluated for impairment | 1,093 |  | 756 |  |  |
Less: allowance for loan and lease losses | 1,103 | 1,038 | 801 | 837 | 866 | 1,315
Commercial Real Estate Portfolio Segment [Member] | Non-owner occupied Loan [Member] |  |  |  |  |  |
Individually evaluated for impairment | 403 |  | 582 |  |  |
Collectively evaluated for impairment | 5,002 |  | 2,800 |  |  |
Less: allowance for loan and lease losses | 5,405 | 5,159 | 3,382 | 3,484 | 3,588 | 2,862
Commercial Real Estate Portfolio Segment [Member] | Multifamily Loan [Member] |  |  |  |  |  |
Individually evaluated for impairment | 0 |  | 0 |  |  |
Collectively evaluated for impairment | 346 |  | 340 |  |  |
Less: allowance for loan and lease losses | 346 | 291 | 340 | 389 | 412 | 474
Residential Portfolio Segment [Member] |  |  |  |  |  |
Individually evaluated for impairment | 21 |  | 28 |  |  |
Collectively evaluated for impairment | 1,350 |  | 698 |  |  |
Less: allowance for loan and lease losses | 1,371 | 1,167 | 726 | 732 | 747 | 761
Commercial And Industrial [Member] |  |  |  |  |  |
Individually evaluated for impairment | 60 |  | 3 |  |  |
Collectively evaluated for impairment | 1,443 |  | 453 |  |  |
Less: allowance for loan and lease losses | 1,503 | 1,105 | 456 | 389 | 539 | 969
Home Equity Lines of Credit [Member] |  |  |  |  |  |
Individually evaluated for impairment | 21 |  | 2 |  |  |
Collectively evaluated for impairment | 1,305 |  | 930 |  |  |
Less: allowance for loan and lease losses | 1,326 | 1,203 | 932 | 941 | 936 | 820
Construction and Other [Member] |  |  |  |  |  |
Individually evaluated for impairment | 0 |  | 0 |  |  |
Collectively evaluated for impairment | 293 |  | 103 |  |  |
Less: allowance for loan and lease losses | 293 | 236 | 103 | 105 | 97 | 100
Consumer Portfolio Segment [Member] |  |  |  |  |  |
Individually evaluated for impairment | 0 |  | 0 |  |  |
Collectively evaluated for impairment | 12 |  | 28 |  |  |
Less: allowance for loan and lease losses | $ 12 | $ 11 | $ 28 | $ 124 | $ 119 | $ 127

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- Definition The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (g) -URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953423-111524 + Details
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- Definition Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (g) -URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953423-111524 + Details
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- Definition Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (g) -URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953423-111524 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (b)(1)(ii) -URI http://asc.fasb.org/extlink&oid=121614798&loc=d3e15032-111544 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953423-111524 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section S99 -Paragraph 4 -Subparagraph (SAB Topic 6.L.1) -URI http://asc.fasb.org/extlink&oid=27010918&loc=d3e74567-122707 + Details
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