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Note 4 - Allowance for Loan Losses, Nonperforming Assets and Impaired Loans (Details) - Loans and Allowance for Loan Losses by Evaluation Method - USD ($) $ in Thousands | Jun. 30, 2015 | Mar. 31, 2015 | Dec. 31, 2014 | Jun. 30, 2014 | Dec. 31, 2013
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Note 4 - Allowance for Loan Losses, Nonperforming Assets and Impaired Loans (Details) - Loans and Allowance for Loan Losses by Evaluation Method [Line Items] |  |  |  |  |
Allowance for loan losses, individually evaluated for impairment | $ 151 |  | $ 282 |  |
Allowance for loan losses, collectively evaluated for impairment | 7,980 |  | 7,981 |  |
Allowance for loan losses | 8,131 | $ 8,227 | 8,263 | $ 7,971 | $ 8,227
Loans individually evaluated for impairment | 14,685 |  | 15,121 |  |
Loans collectively evaluated for impairment | 613,100 |  | 591,198 |  |
Total loans | 627,785 |  | 606,319 |  |
Real Estate Construction Portfolio Segment[Member] |  |  |  |  |
Note 4 - Allowance for Loan Losses, Nonperforming Assets and Impaired Loans (Details) - Loans and Allowance for Loan Losses by Evaluation Method [Line Items] |  |  |  |  |
Allowance for loan losses, individually evaluated for impairment | 0 |  | 0 |  |
Allowance for loan losses, collectively evaluated for impairment | 476 |  | 612 |  |
Allowance for loan losses | 476 | 863 | 612 | 663 | 863
Loans individually evaluated for impairment | 0 |  | 0 |  |
Loans collectively evaluated for impairment | 42,246 |  | 45,562 |  |
Total loans | 42,246 |  | 45,562 |  |
Consumer Real Estate Portfolio Segment [Member] |  |  |  |  |
Note 4 - Allowance for Loan Losses, Nonperforming Assets and Impaired Loans (Details) - Loans and Allowance for Loan Losses by Evaluation Method [Line Items] |  |  |  |  |
Allowance for loan losses, individually evaluated for impairment | 13 |  | 14 |  |
Allowance for loan losses, collectively evaluated for impairment | 1,824 |  | 1,648 |  |
Allowance for loan losses | 1,837 | 1,697 | 1,662 | 1,554 | 1,697
Loans individually evaluated for impairment | 798 |  | 819 |  |
Loans collectively evaluated for impairment | 145,412 |  | 146,220 |  |
Total loans | 146,210 |  | 147,039 |  |
Commercial Real Estate Portfolio Segment [Member] |  |  |  |  |
Note 4 - Allowance for Loan Losses, Nonperforming Assets and Impaired Loans (Details) - Loans and Allowance for Loan Losses by Evaluation Method [Line Items] |  |  |  |  |
Allowance for loan losses, individually evaluated for impairment | 138 |  | 258 |  |
Allowance for loan losses, collectively evaluated for impairment | 3,680 |  | 3,279 |  |
Allowance for loan losses | 3,818 | 3,685 | 3,537 | 3,790 | 3,685
Loans individually evaluated for impairment | 13,375 |  | 13,624 |  |
Loans collectively evaluated for impairment | 309,959 |  | 297,138 |  |
Total loans | 323,334 |  | 310,762 |  |
Commercial Portfolio Segment [Member] |  |  |  |  |
Note 4 - Allowance for Loan Losses, Nonperforming Assets and Impaired Loans (Details) - Loans and Allowance for Loan Losses by Evaluation Method [Line Items] |  |  |  |  |
Allowance for loan losses, individually evaluated for impairment | 0 |  | 10 |  |
Allowance for loan losses, collectively evaluated for impairment | 941 |  | 1,465 |  |
Allowance for loan losses | 941 | 989 | 1,475 | 1,056 | 989
Loans individually evaluated for impairment | 512 |  | 678 |  |
Loans collectively evaluated for impairment | 32,461 |  | 32,735 |  |
Total loans | 32,973 |  | 33,413 |  |
Public Sector and IDA Portfolio Segment[Member] |  |  |  |  |
Note 4 - Allowance for Loan Losses, Nonperforming Assets and Impaired Loans (Details) - Loans and Allowance for Loan Losses by Evaluation Method [Line Items] |  |  |  |  |
Allowance for loan losses, individually evaluated for impairment | 0 |  | 0 |  |
Allowance for loan losses, collectively evaluated for impairment | 486 |  | 327 |  |
Allowance for loan losses | 486 | 132 | 327 | 278 | 132
Loans individually evaluated for impairment | 0 |  | 0 |  |
Loans collectively evaluated for impairment | 53,383 |  | 41,361 |  |
Total loans | 53,383 |  | 41,361 |  |
Consumer Portfolio Segment [Member] |  |  |  |  |
Note 4 - Allowance for Loan Losses, Nonperforming Assets and Impaired Loans (Details) - Loans and Allowance for Loan Losses by Evaluation Method [Line Items] |  |  |  |  |
Allowance for loan losses, individually evaluated for impairment | 0 |  | 0 |  |
Allowance for loan losses, collectively evaluated for impairment | 514 |  | 602 |  |
Allowance for loan losses | 514 | 576 | 602 | 552 | 576
Loans individually evaluated for impairment | 0 |  | 0 |  |
Loans collectively evaluated for impairment | 29,639 |  | 28,182 |  |
Total loans | 29,639 |  | 28,182 |  |
Unallocated Financing Receivables [Member] |  |  |  |  |
Note 4 - Allowance for Loan Losses, Nonperforming Assets and Impaired Loans (Details) - Loans and Allowance for Loan Losses by Evaluation Method [Line Items] |  |  |  |  |
Allowance for loan losses, individually evaluated for impairment | 0 |  | 0 |  |
Allowance for loan losses, collectively evaluated for impairment | 59 |  | 48 |  |
Allowance for loan losses | 59 | $ 285 | 48 | $ 78 | $ 285
Loans individually evaluated for impairment | 0 |  | 0 |  |
Loans collectively evaluated for impairment | 0 |  | 0 |  |
Total 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=49124121&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=49124121&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=49124121&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=49124121&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 30 -Section 50 -Paragraph 2 -Subparagraph (b)(1)(ii) -URI http://asc.fasb.org/extlink&oid=6379141&loc=d3e15032-111544 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Staff Accounting Bulletin (SAB) -Number Topic 6 -Section L -Subsection 1 + Details
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