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Fair Value of Financial Instruments - Impaired Loans and Other Real Estate (Detail) - USD ($) $ in Thousands | Jun. 30, 2018 | Dec. 31, 2017
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Collateral Dependent Impaired Loans [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Assets measured at fair value on a nonrecurring basis, Total | $ 516 | $ 508
Other Real Estate Owned-Residential [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Assets measured at fair value on a nonrecurring basis, Total |  | 22
Other Real Estate Owned-Commercial [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Assets measured at fair value on a nonrecurring basis, Total |  | 266
Fair Value on Nonrecurring Basis [Member] | Collateral Dependent Impaired Loans [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Assets measured at fair value on a nonrecurring basis, Total | 516 | 508
Fair Value on Nonrecurring Basis [Member] | Collateral Dependent Impaired Loans [Member] | Level 3 [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Assets measured at fair value on a nonrecurring basis, Total | $ 516 | 508
Fair Value on Nonrecurring Basis [Member] | Other Real Estate Owned-Residential [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Assets measured at fair value on a nonrecurring basis, Total |  | 22
Fair Value on Nonrecurring Basis [Member] | Other Real Estate Owned-Residential [Member] | Level 3 [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Assets measured at fair value on a nonrecurring basis, Total |  | 22
Fair Value on Nonrecurring Basis [Member] | Other Real Estate Owned-Commercial [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Assets measured at fair value on a nonrecurring basis, Total |  | 266
Fair Value on Nonrecurring Basis [Member] | Other Real Estate Owned-Commercial [Member] | Level 3 [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Assets measured at fair value on a nonrecurring basis, Total |  | $ 266

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- Definition Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=99377789&loc=d3e19207-110258 + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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