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Fair Value of Financial Instruments - Impaired Loans and Other Real Estate (Detail) - USD ($) $ in Thousands | Sep. 30, 2018 | Dec. 31, 2017
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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 | $ 822 | $ 508
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
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
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 | 822 | 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 | $ 822 | 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 Carrying amount of other real estate not separately disclosed, including, but not limited to, real estate investments, real estate loans that qualify as investments in real estate, and premises that are no longer used in operations may also be included in real estate owned. This does not include real estate assets taken in settlement of troubled loans through surrender or foreclosure. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.10(4)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 + Details
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- Definition Aggregate amount of servicing assets that are subsequently measured at fair value and servicing assets that are subsequently measured using the amortization method. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 860 -SubTopic 50 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6469459&loc=d3e122501-111745 + Details
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