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Note 3 - Allowance for Loan Losses, Nonperforming Assets and Impaired Loans - Loans and Allowance for Loan Losses by Evaluation Method (Details) - USD ($) $ in Thousands | Sep. 30, 2020 | Dec. 31, 2019 | Sep. 30, 2019 | Dec. 31, 2018
--- | --- | --- | --- | ---
Allowance for loan losses, individually evaluated for impairment | $ 104 | $ 110 |  |
Allowance for loan losses, collectively evaluated for impairment | 8,324 | 6,753 |  |
Allowance for loan losses | 8,428 | 6,863 | $ 7,262 | $ 7,390
Loans, individually evaluated for impairment | 4,995 | 5,289 |  |
Non-impaired gross loans | 797,804 | 728,738 |  |
Loans | 802,799 | 734,027 |  |
Consumer Real Estate Portfolio Segment [Member] |  |  |  |
Allowance for loan losses, individually evaluated for impairment | 2 | 2 |  |
Allowance for loan losses, collectively evaluated for impairment | 2,160 | 1,893 |  |
Allowance for loan losses | 2,162 | 1,895 | 2,101 | 2,049
Loans, individually evaluated for impairment | 244 | 759 |  |
Non-impaired gross loans | 178,302 | 180,713 |  |
Loans | 178,546 | 181,472 |  |
Commercial Real Estate Portfolio Segment [Member] |  |  |  |
Allowance for loan losses, collectively evaluated for impairment | 3,644 | 2,559 |  |
Allowance for loan losses | 3,644 | 2,559 | 2,699 | 2,798
Loans, individually evaluated for impairment | 3,887 | 3,608 |  |
Non-impaired gross loans | 389,817 | 361,765 |  |
Loans | 393,704 | 365,373 |  |
Commercial Non Real Estate Segment [Member] |  |  |  |
Allowance for loan losses, individually evaluated for impairment | 102 | 108 |  |
Allowance for loan losses, collectively evaluated for impairment | 597 | 447 |  |
Allowance for loan losses | 699 | 555 | 527 | 602
Loans, individually evaluated for impairment | 861 | 918 |  |
Non-impaired gross loans | 100,045 | 45,658 |  |
Loans | 100,906 | 46,576 |  |
Consumer Non Real Estate Portfolio Segment [Member] |  |  |  |
Allowance for loan losses, collectively evaluated for impairment | 597 | 650 |  |
Allowance for loan losses | 597 | 650 | 688 | 750
Loans, individually evaluated for impairment | 3 | 4 |  |
Non-impaired gross loans | 33,611 | 34,535 |  |
Loans | 33,614 | 34,539 |  |
Real Estate Construction Portfolio Segment[Member] |  |  |  |
Allowance for loan losses, collectively evaluated for impairment | 424 | 400 |  |
Allowance for loan losses | 424 | 400 | 454 | 398
Non-impaired gross loans | 36,994 | 42,303 |  |
Loans | 36,994 | 42,303 |  |
Public Sector and IDA Portfolio Segment[Member] |  |  |  |
Allowance for loan losses, collectively evaluated for impairment | 531 | 478 |  |
Allowance for loan losses | 531 | 478 | 490 | 583
Non-impaired gross loans | 59,035 | 63,764 |  |
Loans | 59,035 | 63,764 |  |
Unallocated Financing Receivables [Member] |  |  |  |
Allowance for loan losses, collectively evaluated for impairment | 371 | 326 |  |
Allowance for loan losses | $ 371 | $ 326 | $ 303 | $ 210

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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 The balance of financing receivables 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 (h) -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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