Income Taxes - Additional Information (Detail) - USD ($)	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Income Tax Contingency [Line Items]
Federal statutory tax rate	21.00%	21.00%	21.00%
Deferred tax amounts, valuation allowance recorded	$ 0	$ 0
Uncertain tax positions	0	0
Initial capital contribution commitment	5,500,000
Initial contribution included in other assets	$ 131,000	55,000
NMTC investments [Member]
Income Tax Contingency [Line Items]
Tax Cuts and Jobs Act, Measurement Period Adjustment, Increase (Decrease) in Effective Tax Rate	39.00%
Investments in other assets	$ 26,825,000	$ 29,000,000
FFB Paris Investment Fund, LLC [Member]
Income Tax Contingency [Line Items]
Loan investment	18,000,000
Leveraged loan, invest in other borrowings	$ 21,053,000

Tax Cuts and Jobs Act, Measurement Period Adjustment, Increase (Decrease) in Effective Tax Rate

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Fair value of investment other than investment in equity security, investment in debt security and equity method investment. Includes, but is not limited to, investment in certain entities that calculate net asset value per share. Example includes, but is not limited to, investment in hedge fund, venture capital fund, private equity fund, and real estate partnership or fund.

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Value of property contributed in noncash investing and financing activities.

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- Definition

Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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- Definition

The difference between cost and fair value added or subtracted from paid-in capital, arising from contribution of shares to an ESOP or commitments-to-release ESOP shares.

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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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The aggregate amount of liabilities as of the balance sheet date for obligations incurred in connection with the entity's investments.

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Amount recognized for uncertainty in income taxes classified as current.

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Amount of borrowings classified as other, maturing within one year or the normal operating cycle, if longer.

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