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Note 3 - Allowance for Loan Losses, Nonperforming Assets and Impaired Loans - Nonperforming Assets (Details) - USD ($) $ in Thousands | Mar. 31, 2018 | Dec. 31, 2017 | Mar. 31, 2017
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Nonperforming assets: |  |  |  |  |  |
Nonaccrual loans |  | $ 6 |  | $ 6 |  | $ 1,040
Restructured loans in nonaccrual |  | 2,758 |  | 2,763 |  | 4,640
Total nonperforming loans |  | 2,764 | [1],[2] | 2,769 | [1],[2] | 5,680
Other real estate owned, net |  | 2,741 |  | 2,817 |  | 2,952
Total nonperforming assets |  | $ 5,505 |  | $ 5,586 |  | $ 8,632
Ratio of nonperforming assets to loans, net of unearned income and deferred fees and costs, plus other real estate owned |  | 0.83% |  | 0.83% |  | 1.32%
Ratio of allowance for loan losses to nonperforming loans(1) | [3] | 267.40% |  | 286.20% |  | 145.44%
[1] | Includes current and past due loans in nonaccrual status. Includes impaired loans in nonaccrual status.
[2] | Only classes with past-due or nonaccrual loans are shown.
[3] | The Company defines nonperforming loans as nonaccrual loans and restructured loans that are nonaccrual. Nonperforming loans do not include loans 90 days past due and still accruing or accruing restructured loans.

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- Definition Reflects the percentage derived from dividing the nonperforming assets by total loans net of unearned income deferred fees plus other real estate owned. + References No definition available. + Details
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- Definition Recorded investment in non-restructured loans that are on nonaccrual status as of the balance sheet date. + References No definition available. + Details
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- Definition Refers to ratio of allowance for loan losses to nonperforming loans. + References No definition available. + Details
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- Definition Recorded investment in financing receivables that are on nonaccrual status as of the balance sheet date. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 7 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5111-111524 + Details
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- Definition Carrying amount as of the balance sheet date of land and buildings obtained through foreclosure proceedings or defeasance in full or partial satisfaction of a debt arrangement. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5162-111524 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 45 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=82891408&loc=d3e4437-111522 + Details
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