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Note 4 - Loans and Related Allowance for Loan and Lease Losses - Primary Segments of the Loan Portfolio (Details) - USD ($) $ in Thousands | Dec. 31, 2017 | Dec. 31, 2016
--- | --- | ---
Individually evaluated for impairment | $ 12,109 | $ 12,430
Collectively evaluated for impairment | 911,104 | 596,710
Total loans | 923,213 | 609,140
Commercial And Industrial [Member] |  |
Individually evaluated for impairment | 3,627 | 1,190
Collectively evaluated for impairment | 97,719 | 59,440
Total loans | 101,346 | 60,630
Real Estate Construction Porfolio Segment [Member] |  |
Individually evaluated for impairment | 44 | 913
Collectively evaluated for impairment | 46,973 | 22,796
Total loans | 47,017 | 23,709
Real Estate Mortgage Portfolio Segment [Member] | Residential Loan [Member] |  |
Individually evaluated for impairment | 2,824 | 3,135
Collectively evaluated for impairment | 315,333 | 267,695
Total loans | 318,157 | 270,830
Real Estate Mortgage Portfolio Segment [Member] | Commercial Loans [Member] |  |
Individually evaluated for impairment | 5,610 | 7,187
Collectively evaluated for impairment | 432,337 | 242,303
Total loans | 437,947 | 249,490
Consumer Portfolio Segment [Member] |  |
Individually evaluated for impairment | 4 | 5
Collectively evaluated for impairment | 18,742 | 4,476
Total loans | $ 18,746 | $ 4,481

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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 before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. 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 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5074-111524 + Details
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