Annual report [Section 13 and 15(d), not S-K Item 405]

Fair Value Measurements - Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail)

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Fair Value Measurements - Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) - USD ($)
$ in Thousands
Dec. 31, 2024
Dec. 31, 2023
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Securities available for sale $ 905,798 $ 865,739
Derivative Asset, Statement of Financial Position [Extensible Enumeration] Prepaid Expense and Other Assets Prepaid Expense and Other Assets
Derivative Liability, Statement of Financial Position [Extensible Enumeration] Accrued Liabilities and Other Liabilities Accrued Liabilities and Other Liabilities
U.S. Treasury securities    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Securities available for sale $ 88,929 $ 85,488
Collateralized mortgage obligations    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Securities available for sale 173,556 97,411
Debt securities    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Securities available for sale 122,816 124,625
Total U.S. government agency and sponsored agency obligations    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Securities available for sale 751,860 712,355
Municipal bonds-tax exempt    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Securities available for sale 65,009 67,896
Recurring Basis    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Securities available for sale 905,798 865,739
Recurring Basis | U.S. Treasury securities    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Securities available for sale 88,929 85,488
Recurring Basis | Derivative financial instruments    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Derivative financial instruments, Assets 4,690 5,920
Derivative financial instruments, Liabilities 5,292 6,245
Recurring Basis | Collateralized mortgage obligations    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Securities available for sale 173,556 97,411
Recurring Basis | Debt securities    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Securities available for sale 122,816 124,625
Recurring Basis | Total U.S. government agency and sponsored agency obligations    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Securities available for sale 751,860 712,355
Recurring Basis | Municipal bonds-tax exempt    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Securities available for sale 65,009 67,896
Recurring Basis | Mortgage-backed securities - commercial | Mortgage-backed securities    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Securities available for sale 62,916 47,991
Recurring Basis | Mortgage-backed securities - residential | Mortgage-backed securities    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Securities available for sale 392,572 442,328
Recurring Basis | Quoted Prices in Active Markets for Identical Assets    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Securities available for sale 88,929 85,488
Recurring Basis | Quoted Prices in Active Markets for Identical Assets | U.S. Treasury securities    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Securities available for sale 88,929 85,488
Recurring Basis | Quoted Prices in Active Markets for Identical Assets | Derivative financial instruments    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Derivative financial instruments, Assets 0 0
Derivative financial instruments, Liabilities 0 0
Recurring Basis | Quoted Prices in Active Markets for Identical Assets | Collateralized mortgage obligations    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Securities available for sale 0 0
Recurring Basis | Quoted Prices in Active Markets for Identical Assets | Debt securities    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Securities available for sale 0 0
Recurring Basis | Quoted Prices in Active Markets for Identical Assets | Total U.S. government agency and sponsored agency obligations    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Securities available for sale 0 0
Recurring Basis | Quoted Prices in Active Markets for Identical Assets | Municipal bonds-tax exempt    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Securities available for sale 0 0
Recurring Basis | Quoted Prices in Active Markets for Identical Assets | Mortgage-backed securities - commercial | Mortgage-backed securities    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Securities available for sale 0 0
Recurring Basis | Quoted Prices in Active Markets for Identical Assets | Mortgage-backed securities - residential | Mortgage-backed securities    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Securities available for sale 0 0
Recurring Basis | Significant Observable Inputs with No Active Market with Identical Characteristics    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Securities available for sale 816,869 780,251
Recurring Basis | Significant Observable Inputs with No Active Market with Identical Characteristics | U.S. Treasury securities    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Securities available for sale 0 0
Recurring Basis | Significant Observable Inputs with No Active Market with Identical Characteristics | Derivative financial instruments    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Derivative financial instruments, Assets 4,690 5,920
Derivative financial instruments, Liabilities 5,292 6,245
Recurring Basis | Significant Observable Inputs with No Active Market with Identical Characteristics | Collateralized mortgage obligations    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Securities available for sale 173,556 97,411
Recurring Basis | Significant Observable Inputs with No Active Market with Identical Characteristics | Debt securities    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Securities available for sale 122,816 124,625
Recurring Basis | Significant Observable Inputs with No Active Market with Identical Characteristics | Total U.S. government agency and sponsored agency obligations    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Securities available for sale 751,860 712,355
Recurring Basis | Significant Observable Inputs with No Active Market with Identical Characteristics | Municipal bonds-tax exempt    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Securities available for sale 65,009 67,896
Recurring Basis | Significant Observable Inputs with No Active Market with Identical Characteristics | Mortgage-backed securities - commercial | Mortgage-backed securities    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Securities available for sale 62,916 47,991
Recurring Basis | Significant Observable Inputs with No Active Market with Identical Characteristics | Mortgage-backed securities - residential | Mortgage-backed securities    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Securities available for sale 392,572 442,328
Recurring Basis | Significant Unobservable Inputs    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Securities available for sale 0 0
Recurring Basis | Significant Unobservable Inputs | U.S. Treasury securities    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Securities available for sale 0 0
Recurring Basis | Significant Unobservable Inputs | Derivative financial instruments    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Derivative financial instruments, Assets 0 0
Derivative financial instruments, Liabilities 0 0
Recurring Basis | Significant Unobservable Inputs | Collateralized mortgage obligations    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Securities available for sale 0 0
Recurring Basis | Significant Unobservable Inputs | Debt securities    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Securities available for sale 0 0
Recurring Basis | Significant Unobservable Inputs | Total U.S. government agency and sponsored agency obligations    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Securities available for sale 0 0
Recurring Basis | Significant Unobservable Inputs | Municipal bonds-tax exempt    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Securities available for sale 0 0
Recurring Basis | Significant Unobservable Inputs | Mortgage-backed securities - commercial | Mortgage-backed securities    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Securities available for sale 0 0
Recurring Basis | Significant Unobservable Inputs | Mortgage-backed securities - residential | Mortgage-backed securities    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Securities available for sale $ 0 $ 0