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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, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Balance | $ 8,300 | $ 8,297 | $ 8,263
Charge-offs | (819) | (1,806) | (2,120)
Recoveries | 287 | 159 | 145
Provision for loan losses | 157 | 1,650 | 2,009
Balance | 7,925 | 8,300 | 8,297
Real Estate Construction Portfolio Segment[Member] |  |  |
Balance | 438 | 576 | 612
Charge-offs | 0 | (29) |
Recoveries | 0 | 0 | 0
Provision for loan losses | (101) | (109) | (36)
Balance | 337 | 438 | 576
Consumer Real Estate Portfolio Segment [Member] |  |  |
Balance | 1,830 | 1,866 | 1,662
Charge-offs | (146) | (133) | (205)
Recoveries | 1 | 2 | 2
Provision for loan losses | 342 | 95 | 407
Balance | 2,027 | 1,830 | 1,866
Commercial Real Estate Portfolio Segment [Member] |  |  |
Balance | 3,738 | 4,109 | 3,537
Charge-offs | (139) | (488) | (1,114)
Recoveries | 131 | 83 | 49
Provision for loan losses | (686) | 34 | 1,637
Balance | 3,044 | 3,738 | 4,109
Commercial Non Real Estate Segment [Member] |  |  |
Balance | 1,063 | 655 | 1,475
Charge-offs | (82) | (883) | (490)
Recoveries | 23 | 10 | 1
Provision for loan losses | 68 | (1,281) | (331)
Balance | 1,072 | 1,063 | 655
Public Sector and IDA Portfolio Segment[Member] |  |  |
Balance | 330 | 436 | 327
Charge-offs | 0 | 0 | 0
Recoveries | 0 | 0 | 0
Provision for loan losses | 89 | (106) | 109
Balance | 419 | 330 | 436
Consumer Non Real Estate Portfolio Segment [Member] |  |  |
Balance | 644 | 627 | 602
Charge-offs | (452) | (273) | (311)
Recoveries | 132 | 64 | 93
Provision for loan losses | 383 | 226 | 243
Balance | 707 | 644 | 627
Unallocated Financing Receivables [Member] |  |  |
Balance | 257 | 28 | 48
Charge-offs | 0 | 0 | 0
Recoveries | 0 | 0 | 0
Provision for loan losses | 62 | 229 | (20)
Balance | $ 319 | $ 257 | $ 28

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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=84173941&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=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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