Investment Securities - Additional Information (Detail) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Schedule Of Investments [Line Items]
Federal Reserve Bank of Richmond (“FRB”) stock	$ 2,205
Other investments	1,484
Federal Home Loan Bank of Atlanta and Treasury Board of Virginia [Member]
Schedule Of Investments [Line Items]
Securities pledged	40,645	$ 68,255
Federal Home Loan Bank of Atlanta [Member]
Schedule Of Investments [Line Items]
Federal home loan bank stock	$ 5,752

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).

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 325
-Section 45
-Paragraph 1
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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).

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Amount of investments classified as other.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
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Sum of the carrying amounts as of the date of the latest financial statement presented of securities which are owned but transferred to another party to serve as collateral to partially or fully secure a debt obligation, repurchase agreement or other current or potential obligation, and for which the transferee is not permitted to sell or re-pledge them to an unrelated party.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 30
-Section 50
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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.

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