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Note 5 - Allowance for Loan Losses, Nonperforming Assets and Impaired Loans - Loans and Allowance for Loan Losses by Evaluation Method (Details) - USD ($) $ in Thousands | Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014
--- | --- | --- | --- | ---
Allowance for loan losses, individually evaluated for impairment | $ 177 | $ 26 |  |
Allowance for loan losses, collectively evaluated for impairment | 7,748 | 8,274 |  |
Allowance for loan losses | 7,925 | 8,300 | $ 8,297 | $ 8,263
Loans, individually evaluated for impairment | 11,924 | 9,173 |  |
Loans, collectively evaluated for impairment | 656,758 | 639,373 |  |
Loans | 668,682 | 648,546 |  |
Real Estate Construction Portfolio Segment[Member] |  |  |  |
Allowance for loan losses, individually evaluated for impairment | 0 | 0 |  |
Allowance for loan losses, collectively evaluated for impairment | 337 | 438 |  |
Allowance for loan losses | 337 | 438 | 576 | 612
Loans, individually evaluated for impairment | 2,882 | 270 |  |
Loans, collectively evaluated for impairment | 31,812 | 36,075 |  |
Loans | 34,694 | 36,345 |  |
Consumer Real Estate Portfolio Segment [Member] |  |  |  |
Allowance for loan losses, individually evaluated for impairment | 16 | 25 |  |
Allowance for loan losses, collectively evaluated for impairment | 2,011 | 1,805 |  |
Allowance for loan losses | 2,027 | 1,830 | 1,866 | 1,662
Loans, individually evaluated for impairment | 1,267 | 877 |  |
Loans, collectively evaluated for impairment | 165,698 | 156,841 |  |
Loans | 166,965 | 157,718 |  |
Commercial Real Estate Portfolio Segment [Member] |  |  |  |
Allowance for loan losses, individually evaluated for impairment | 0 | 1 |  |
Allowance for loan losses, collectively evaluated for impairment | 3,044 | 3,737 |  |
Allowance for loan losses | 3,044 | 3,738 | 4,109 | 3,537
Loans, individually evaluated for impairment | 6,516 | 7,782 |  |
Loans, collectively evaluated for impairment | 333,898 | 328,675 |  |
Loans | 340,414 | 336,457 |  |
Commercial Non Real Estate Segment [Member] |  |  |  |
Allowance for loan losses, individually evaluated for impairment | 160 | 0 |  |
Allowance for loan losses, collectively evaluated for impairment | 912 | 1,063 |  |
Allowance for loan losses | 1,072 | 1,063 | 655 | 1,475
Loans, individually evaluated for impairment | 1,229 | 241 |  |
Loans, collectively evaluated for impairment | 39,289 | 38,783 |  |
Loans | 40,518 | 39,024 |  |
Public Sector and IDA Portfolio Segment[Member] |  |  |  |
Allowance for loan losses, individually evaluated for impairment | 0 | 0 |  |
Allowance for loan losses, collectively evaluated for impairment | 419 | 330 |  |
Allowance for loan losses | 419 | 330 | 436 | 327
Loans, individually evaluated for impairment | 0 | 0 |  |
Loans, collectively evaluated for impairment | 51,443 | 45,474 |  |
Loans | 51,443 | 45,474 |  |
Consumer Non Real Estate Portfolio Segment [Member] |  |  |  |
Allowance for loan losses, individually evaluated for impairment | 1 | 0 |  |
Allowance for loan losses, collectively evaluated for impairment | 706 | 644 |  |
Allowance for loan losses | 707 | 644 | 627 | 602
Loans, individually evaluated for impairment | 30 | 3 |  |
Loans, collectively evaluated for impairment | 34,618 | 33,525 |  |
Loans | 34,648 | 33,528 |  |
Unallocated Financing Receivables [Member] |  |  |  |
Allowance for loan losses, individually evaluated for impairment | 0 | 0 |  |
Allowance for loan losses, collectively evaluated for impairment | 319 | 257 |  |
Allowance for loan losses | 319 | 257 | $ 28 | $ 48
Loans, individually evaluated for impairment | 0 | 0 |  |
Loans, collectively evaluated for impairment | 0 | 0 |  |
Loans | $ 0 | $ 0 |  |

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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://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (g) -URI http://asc.fasb.org/extlink&oid=84173941&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://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (g) -URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524 + Details
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- Definition The balance of financing receivables that were collectively evaluated for impairment. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (h) -URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524 + Details
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- Definition The balance of financing receivables that were individually evaluated for impairment. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (h) -URI http://asc.fasb.org/extlink&oid=84173941&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://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (g) -URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.7(d)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 4: http://www.xbrl.org/2003/role/presentationRef -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 Reference 5: http://www.xbrl.org/2003/role/presentationRef -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=82894903&loc=d3e15032-111544 + Details
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- Definition Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=82891408&loc=d3e4428-111522 + Details
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