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Note 7 - Loans and Related Allowance for Loan Losses - Primary Segments of the Loan Portfolio (Details) - USD ($) $ in Thousands | Jun. 30, 2017 | Mar. 31, 2017 | Dec. 31, 2016 | Jun. 30, 2016 | Mar. 31, 2016 | Dec. 31, 2015
--- | --- | --- | --- | --- | --- | ---
Individually evaluated for impairment | $ 17,008 |  | $ 12,430 |  |  |
Collectively evaluated for impairment | 850,856 |  | 596,710 |  |  |
Total loans | 867,864 |  | 609,140 |  |  |
Collectively evaluated for impairment | 4,873 |  | 6,071 |  |  |
Total ending allowance balance | 6,605 | $ 6,720 | 6,598 | $ 6,366 | $ 6,357 | $ 6,385
Individually evaluated for impairment | 1,732 |  | 527 |  |  |
Commercial And Industrial [Member] |  |  |  |  |  |
Individually evaluated for impairment | 3,084 |  | 1,190 |  |  |
Collectively evaluated for impairment | 94,076 |  | 59,440 |  |  |
Total loans | 97,160 |  | 60,630 |  |  |
Collectively evaluated for impairment | 278 |  | 358 |  |  |
Total ending allowance balance | 613 | 616 | 448 | 484 | 583 | 867
Individually evaluated for impairment | 335 |  | 90 |  |  |
Real Estate Construction Porfolio Segment [Member] |  |  |  |  |  |
Individually evaluated for impairment | 541 |  | 913 |  |  |
Collectively evaluated for impairment | 35,030 |  | 22,796 |  |  |
Total loans | 35,571 |  | 23,709 |  |  |
Collectively evaluated for impairment | 202 |  | 172 |  |  |
Total ending allowance balance | 202 | 186 | 172 | 159 | 247 | 276
Individually evaluated for impairment |  |  |  |  |  |
Real Estate Mortgage Portfolio Segment [Member] | Residential Loan [Member] |  |  |  |  |  |
Individually evaluated for impairment | 3,170 |  | 3,135 |  |  |
Collectively evaluated for impairment | 305,349 |  | 267,695 |  |  |
Total loans | 308,519 |  | 270,830 |  |  |
Collectively evaluated for impairment | 1,577 |  | 2,567 |  |  |
Total ending allowance balance | 1,767 | 2,523 | 2,818 | 2,788 | 2,716 | 3,139
Individually evaluated for impairment | 190 |  | 251 |  |  |
Real Estate Mortgage Portfolio Segment [Member] | Commercial Loans [Member] |  |  |  |  |  |
Individually evaluated for impairment | 10,209 |  | 7,187 |  |  |
Collectively evaluated for impairment | 396,461 |  | 242,303 |  |  |
Total loans | 406,670 |  | 249,490 |  |  |
Collectively evaluated for impairment | 2,805 |  | 2,949 |  |  |
Total ending allowance balance | 4,012 | 3,378 | 3,135 | 2,909 | 2,783 | 2,078
Individually evaluated for impairment | 1,207 |  | 186 |  |  |
Consumer Portfolio Segment [Member] |  |  |  |  |  |
Individually evaluated for impairment | 4 |  | 5 |  |  |
Collectively evaluated for impairment | 19,940 |  | 4,476 |  |  |
Total loans | 19,944 |  | 4,481 |  |  |
Collectively evaluated for impairment | 11 |  | 25 |  |  |
Total ending allowance balance | 11 | $ 17 | 25 | $ 26 | $ 28 | $ 25
Individually evaluated for impairment |  |  |  |  |  |

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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 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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