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Note 5 - Allowance for Loan Losses, Nonperforming Assets and Impaired Loans - Allowance for Loan Losses (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014
Balance | $ 8,297 | $ 8,263 | $ 8,227
Charge-offs | (1,806) | (2,120) | (1,860)
Recoveries | 159 | 145 | 255
Provision for loan losses | 1,650 | 2,009 | 1,641
Balance | 8,300 | 8,297 | 8,263
Real Estate Construction Portfolio Segment[Member] |  |  |
Balance | 576 | 612 | 863
Charge-offs | (29) | 0 | (2)
Recoveries | 0 | 0 | 0
Provision for loan losses | (109) | (36) | (249)
Balance | 438 | 576 | 612
Consumer Real Estate Portfolio Segment [Member] |  |  |
Balance | 1,866 | 1,662 | 1,697
Charge-offs | (133) | (205) | (222)
Recoveries | 2 | 2 | 0
Provision for loan losses | 95 | 407 | 187
Balance | 1,830 | 1,866 | 1,662
Commercial Real Estate Portfolio Segment [Member] |  |  |
Balance | 4,109 | 3,537 | 3,685
Charge-offs | (488) | (1,114) | (1,201)
Recoveries | 83 | 49 | 50
Provision for loan losses | 34 | 1,637 | 1,003
Balance | 3,738 | 4,109 | 3,537
Commercial Non Real Estate Segment [Member] |  |  |
Balance | 655 | 1,475 | 989
Charge-offs | (883) | (490) | (89)
Recoveries | 10 | 1 | 132
Provision for loan losses | 1,281 | (331) | 443
Balance | 1,063 | 655 | 1,475
Public Sector and IDA Portfolio Segment[Member] |  |  |
Balance | 436 | 327 | 132
Charge-offs | 0 | 0 | 0
Recoveries | 0 | 0 | 0
Provision for loan losses | (106) | 109 | 195
Balance | 330 | 436 | 327
Consumer Non Real Estate Portfolio Segment [Member] |  |  |
Balance | 627 | 602 | 576
Charge-offs | (273) | (311) | (346)
Recoveries | 64 | 93 | 73
Provision for loan losses | 226 | 243 | 299
Balance | 644 | 627 | 602
Unallocated Financing Receivables [Member] |  |  |
Balance | 28 | 48 | 285
Charge-offs | 0 | 0 | 0
Recoveries | 0 | 0 | 0
Provision for loan losses | 229 | (20) | (237)
Balance | $ 257 | $ 28 | $ 48

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- Definition Amount of recovery of financing receivables doubtful of collection that were previously charged off. + 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 (c)(4) -URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953423-111524 + Details
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- Definition Amount of direct write-downs of financing receivables charged against the allowance. + 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 (c)(3) -URI http://asc.fasb.org/extlink&oid=66008989&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=66008989&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=66008989&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=6379141&loc=d3e15032-111544 + Details
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