Long-Term Borrowings - Additional Information (Detail) - USD ($)	6 Months Ended
Jun. 30, 2022	Dec. 31, 2021
Debt Instrument [Line Items]
Unused borrowing amount	$ 7,679,664
Outstanding balances of debentures	$ 276,161,000	$ 275,323,000
Maximum time to defer payment of interest on subordinate debt	5 years
Advances from Federal Home Loan Banks	$ 510,918,000	532,199,000
Federal Home Loan Bank, Advances, Activity for Year, Average Interest Rate for Year	1.29%
Debt, Weighted Average Interest Rate	0.42%
Community Bankers Trust [Member]
Debt Instrument [Line Items]
Outstanding balances of debentures	$ 9,882,000	$ 9,872,000
Fixed To Floating Rate Subordinated Notes [Member] \| Carolina Financial [Member]
Debt Instrument [Line Items]
Business combination subordinated notes assumed Face Value	10,000,000
LIBOR Indexed Floating Rate Subordinated Note [Member] \| Community Bankers Trust [Member]
Debt Instrument [Line Items]
Business combination subordinated notes assumed Face Value	$ 4,124,000

Maximum time to defer payment of interest on subordinate debt.

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Amount of borrowings as of the balance sheet date from the Federal Home Loan Bank, which are primarily used to cover shortages in the required reserve balance and liquidity shortages.

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Face (par) amount of debt instrument at time of issuance.

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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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Weighted average interest rate of debt outstanding.

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The calculated weighted average interest rate for Federal Home Loan Bank advances for the period ended as of the Balance Sheet date.

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Amount of advances or credit lines available from the Federal Home Loan Bank (FHLB).

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Carrying value as of the balance sheet date of long-term debt (with maturities initially due after one year or beyond the operating cycle if longer) identified as Junior Subordinated Notes, which have a lower priority than senior instruments, excluding current portion.

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