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Securities - Composition of Restricted Securities (Detail) - USD ($) $ in Thousands | Mar. 31, 2018 | Dec. 31, 2017
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Investments, Debt and Equity Securities [Abstract] |  |  |
Federal Home Loan Bank stock | $ 665 | $ 645 |
Federal Reserve Bank stock | 875 | 875 |
Community Bankers’ Bank stock | 50 | 50 |
Total restricted securities | $ 1,590 | $ 1,570 | [1]
[1] | Derived from audited consolidated financial statements.

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- Definition Community bankers bank stock. + References No definition available. + Details
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- Definition Federal Home Loan Bank (FHLB) stock represents an equity interest in a FHLB. It does not have a readily determinable fair value because its ownership is restricted and it lacks a market (liquidity). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 325 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=75031641&loc=d3e63345-112809 + Details
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- Definition Federal Reserve Bank stock represents an equity interest in the Federal Reserve Bank. It does not have a readily determinable fair value because its ownership is restricted and it lacks a market (liquidity). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 325 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=75031641&loc=d3e63345-112809 + Details
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- References No definition available. + Details
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- Definition Investments which are not defined as or included in marketable (debt, equity, or other) securities whose use is restricted in whole or in part, generally by contractual agreements or regulatory requirements. For use in an unclassified balance sheet. + References No definition available. + Details
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