Income Taxes - Additional Information (Detail) - USD ($) |
3 Months Ended | 6 Months Ended | |||
|---|---|---|---|---|---|
Jun. 30, 2026 |
Jun. 30, 2025 |
Jun. 30, 2026 |
Jun. 30, 2025 |
Dec. 31, 2025 |
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| Income Taxes [Line Items] | |||||
| Federal statutory tax rate | 21.00% | ||||
| Income tax expense | $ 15,575,000 | $ 15,078,000 | $ 31,860,000 | $ 28,888,000 | |
| Effective tax rates on pre-tax income | 18.20% | 18.40% | 17.80% | 18.40% | |
| Unfunded contingent commitments | $ 30,360,000 | $ 30,360,000 | $ 21,114,000 | ||
| Leveraged loan, invest in other borrowings | 21,053,000 | 21,053,000 | |||
| Low Income Housing Tax Credit Investments [Member] | |||||
| Income Taxes [Line Items] | |||||
| Investments | 35,255,000 | $ 35,255,000 | 27,500,000 | ||
| NMTC Investments [Member] | |||||
| Income Taxes [Line Items] | |||||
| Tax Benefit Percent of Qualified Investments | 39.00% | ||||
| Investment related liabilities | 22,475,000 | $ 22,475,000 | 23,128,000 | ||
| 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 | ||
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- Definition Income Taxes [Line Items] No definition available.
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- Definition Tax Cuts and Jobs Act, Measurement Period Adjustment, Increase (Decrease) in Effective Tax Rate No definition available.
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- Definition Unfunded Contingent Commitments No definition available.
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- Definition 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. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Percentage of domestic federal statutory tax rate applicable to pretax income (loss). Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition The aggregate amount of liabilities as of the balance sheet date for obligations incurred in connection with the entity's investments. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Sum of the carrying amounts as of the balance sheet date of all investments. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of borrowings classified as other, maturing within one year or the normal operating cycle, if longer. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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