Income Taxes - Additional Information (Detail) - USD ($)	3 Months Ended	12 Months Ended
Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
Income Taxes [Line Items]
Federal statutory tax rate	21.00%
Income tax expense	$ 10,341,000	$ 11,054,000
Effective tax rates on pre-tax income	15.59%	16.26%
Initial capital contribution commitment	$ 5,500,000
Initial contribution included in other assets	$ 55,000		$ 55,000
Leveraged loan, invest in other borrowings			21,053,000
Investment related liabilities		$ 0
NMTC Investments [Member]
Income Taxes [Line Items]
Tax benefits rate	0.39
Investment related liabilities		$ 0
FFB Paris Investment Fund, LLC [Member]
Income Taxes [Line Items]
Initial contribution included in other assets	$ 29,000,000		29,000,000
Loan investment	18,000,000		18,000,000
Leveraged loan, invest in other borrowings	$ 21,053,000		$ 21,053,000

Income Taxes [Line Items]

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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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- Definition

Value of property contributed in noncash investing and financing activities.

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- Definition

Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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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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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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

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Percentage of increase (decrease) in effective tax rate for measurement period adjustment from accounting for tax effect pursuant to Tax Cuts and Jobs Act.

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