Fair Value Measurement and Fair Value of Financial Instruments - Fair Value of Financial Assets and Liabilities Measured on Recurring Basis (Detail) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Assets:
Fair Value	$ 1,054,312	$ 769,956
Equity securities, at fair value	17,283	17,368
Fair Value, Measurements, Recurring
Assets:
Fair Value	1,054,312	769,956
Equity securities, at fair value	17,283	17,368
Derivative assets	97,848	43,799
Total Assets	1,169,443	831,123
Liabilities:
Derivative liabilities	97,848	43,799
Total Liabilities	97,848	43,799
Quoted Prices in Active Markets for Identical Assets (Level 1) \| Fair Value, Measurements, Recurring
Assets:
Fair Value	162,438	104,861
Equity securities, at fair value	0	0
Derivative assets	0	0
Total Assets	162,438	104,861
Liabilities:
Derivative liabilities	0	0
Total Liabilities	0	0
Significant Other Observable Inputs (Level 2) \| Fair Value, Measurements, Recurring
Assets:
Fair Value	891,874	665,095
Equity securities, at fair value	17,283	17,368
Derivative assets	97,848	43,799
Total Assets	1,007,005	726,262
Liabilities:
Derivative liabilities	97,848	43,799
Total Liabilities	97,848	43,799
Significant Unobservable Inputs (Level 3) \| Fair Value, Measurements, Recurring
Assets:
Fair Value	0	0
Equity securities, at fair value	0	0
Derivative assets	0	0
Total Assets	0	0
Liabilities:
Derivative liabilities	0	0
Total Liabilities	0	0
U.S. Treasury and U.S. government agencies
Assets:
Fair Value	355,639	203,387
U.S. Treasury and U.S. government agencies \| Fair Value, Measurements, Recurring
Assets:
Fair Value	355,639	203,387
U.S. Treasury and U.S. government agencies \| Quoted Prices in Active Markets for Identical Assets (Level 1) \| Fair Value, Measurements, Recurring
Assets:
Fair Value	162,438	104,861
U.S. Treasury and U.S. government agencies \| Significant Other Observable Inputs (Level 2) \| Fair Value, Measurements, Recurring
Assets:
Fair Value	193,201	98,526
U.S. Treasury and U.S. government agencies \| Significant Unobservable Inputs (Level 3) \| Fair Value, Measurements, Recurring
Assets:
Fair Value	0	0
Mortgage-backed securities, residential \| Fair Value, Measurements, Recurring
Assets:
Fair Value	310,613	237,975
Mortgage-backed securities, residential \| Quoted Prices in Active Markets for Identical Assets (Level 1) \| Fair Value, Measurements, Recurring
Assets:
Fair Value	0	0
Mortgage-backed securities, residential \| Significant Other Observable Inputs (Level 2) \| Fair Value, Measurements, Recurring
Assets:
Fair Value	310,613	237,975
Mortgage-backed securities, residential \| Significant Unobservable Inputs (Level 3) \| Fair Value, Measurements, Recurring
Assets:
Fair Value	0	0
Collateralized mortgage obligations, residential \| Fair Value, Measurements, Recurring
Assets:
Fair Value	154,058	191,291
Collateralized mortgage obligations, residential \| Quoted Prices in Active Markets for Identical Assets (Level 1) \| Fair Value, Measurements, Recurring
Assets:
Fair Value	0	0
Collateralized mortgage obligations, residential \| Significant Other Observable Inputs (Level 2) \| Fair Value, Measurements, Recurring
Assets:
Fair Value	154,058	191,291
Collateralized mortgage obligations, residential \| Significant Unobservable Inputs (Level 3) \| Fair Value, Measurements, Recurring
Assets:
Fair Value	0	0
Mortgage-backed securities, multifamily
Assets:
Fair Value	785	1,741
Mortgage-backed securities, multifamily \| Fair Value, Measurements, Recurring
Assets:
Fair Value	785	1,741
Mortgage-backed securities, multifamily \| Quoted Prices in Active Markets for Identical Assets (Level 1) \| Fair Value, Measurements, Recurring
Assets:
Fair Value	0	0
Mortgage-backed securities, multifamily \| Significant Other Observable Inputs (Level 2) \| Fair Value, Measurements, Recurring
Assets:
Fair Value	785	1,741
Mortgage-backed securities, multifamily \| Significant Unobservable Inputs (Level 3) \| Fair Value, Measurements, Recurring
Assets:
Fair Value	0	0
Collateralized mortgage obligations, multifamily \| Fair Value, Measurements, Recurring
Assets:
Fair Value	46,333	32,519
Collateralized mortgage obligations, multifamily \| Quoted Prices in Active Markets for Identical Assets (Level 1) \| Fair Value, Measurements, Recurring
Assets:
Fair Value	0	0
Collateralized mortgage obligations, multifamily \| Significant Other Observable Inputs (Level 2) \| Fair Value, Measurements, Recurring
Assets:
Fair Value	46,333	32,519
Collateralized mortgage obligations, multifamily \| Significant Unobservable Inputs (Level 3) \| Fair Value, Measurements, Recurring
Assets:
Fair Value	0	0
Asset-backed securities
Assets:
Fair Value	52,395	52,584
Asset-backed securities \| Fair Value, Measurements, Recurring
Assets:
Fair Value	52,395	52,584
Asset-backed securities \| Quoted Prices in Active Markets for Identical Assets (Level 1) \| Fair Value, Measurements, Recurring
Assets:
Fair Value	0	0
Asset-backed securities \| Significant Other Observable Inputs (Level 2) \| Fair Value, Measurements, Recurring
Assets:
Fair Value	52,395	52,584
Asset-backed securities \| Significant Unobservable Inputs (Level 3) \| Fair Value, Measurements, Recurring
Assets:
Fair Value	0	0
Obligations of states and political subdivisions
Assets:
Fair Value	21,122
Obligations of states and political subdivisions \| Fair Value, Measurements, Recurring
Assets:
Fair Value	21,122
Obligations of states and political subdivisions \| Quoted Prices in Active Markets for Identical Assets (Level 1) \| Fair Value, Measurements, Recurring
Assets:
Fair Value	0
Obligations of states and political subdivisions \| Significant Other Observable Inputs (Level 2) \| Fair Value, Measurements, Recurring
Assets:
Fair Value	21,122
Obligations of states and political subdivisions \| Significant Unobservable Inputs (Level 3) \| Fair Value, Measurements, Recurring
Assets:
Fair Value	0
Corporate debt securities
Assets:
Fair Value	113,367	50,459
Corporate debt securities \| Fair Value, Measurements, Recurring
Assets:
Fair Value	113,367	50,459
Corporate debt securities \| Quoted Prices in Active Markets for Identical Assets (Level 1) \| Fair Value, Measurements, Recurring
Assets:
Fair Value	0	0
Corporate debt securities \| Significant Other Observable Inputs (Level 2) \| Fair Value, Measurements, Recurring
Assets:
Fair Value	113,367	50,459
Corporate debt securities \| Significant Unobservable Inputs (Level 3) \| Fair Value, Measurements, Recurring
Assets:
Fair Value	$ 0	$ 0

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Amount excluding accrued interest, of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

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