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Securities - Composition of Restricted Securities (Detail) - USD ($) $ in Thousands | Sep. 30, 2015 | Dec. 31, 2014
--- | --- | ---
Federal Home Loan Bank Stock and Federal Reserve Bank Stock [Abstract] |  |
Federal Home Loan Bank stock | $ 466 | $ 470
Federal Reserve Bank stock | 875 | 846
Community Bankers' Bank stock | 50 | 50
Total Restricted Securities | $ 1,391 | $ 1,366

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- Definition Community bankers bank stock. + References No definition available. + Details
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Balance Type: | debit
Period Type: | instant

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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=6478792&loc=d3e63345-112809 + Details
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Balance Type: | debit
Period Type: | instant

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- References No definition available. + Details
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Balance Type: | na
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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=6478792&loc=d3e63345-112809 + 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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Data Type: | xbrli:monetaryItemType
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