Investments - Additional Information (Detail) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Schedule Of Investments [Line Items]
Securities sold under repurchase agreements	$ 1,198
Securities pledged as collateral fair value	3,000
Federal home loan bank stock	8,200	$ 5,800
Federal reserve bank stock	4,900	2,200
Correspondent bank stock	468	248
Other equity investments	1,200	3,000
FHLB [Member]
Schedule Of Investments [Line Items]
Securities pledged	23,600	29,400
Treasury Board Commonwealth of Virginia [Member]
Schedule Of Investments [Line Items]
Securities pledged	$ 11,900	$ 12,500

Correspondent bank stock.

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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).

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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).

+ References

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Amount of investments classified as other.

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The fair value, as of the date of each statement of financial position presented, of securities which are owned but transferred to serve as collateral for the payment of repurchase agreements, and that are reclassified and separately reported in the statement of financial position because the transferee has the right by contract or custom to sell or re-pledge them.

+ References

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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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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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Amount, after the effects of master netting arrangements, of funds outstanding borrowed in the form of a security repurchase agreement between the entity and another party for the sale and repurchase of identical or substantially the same securities at a date certain for a specified price. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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