Income Taxes - Additional Information (Detail) - USD ($)	3 Months Ended		12 Months Ended
	Mar. 31, 2025	Mar. 31, 2024	Dec. 31, 2024
Income Taxes [Line Items]
Federal statutory tax rate	21.00%
Income tax expense	$ 13,810,000	$ 11,480,000
Effective tax rates on pre-tax income	18.38%	17.70%
Initial contribution included in other assets	$ 4,695,000	$ 978,000	$ 3,925,000
Additional Contribution Of Property			7,000,000
Leveraged loan, invest in other borrowings	21,053,000
Maximum [Member]
Income Taxes [Line Items]
Initial contribution included in other assets	$ 5,500,000
NMTC Investments [Member]
Income Taxes [Line Items]
Tax Benefit Percent of Qualified Investments	0.39
Investment related liabilities	$ 24,106,000	25,411,000	24,433,000
FFB Paris Investment Fund, LLC [Member]
Income Taxes [Line Items]
Loan investment	18,000,000	18,000,000	18,000,000
Leveraged loan, invest in other borrowings	$ 21,053,000	$ 21,053,000	$ 21,053,000