Fair Value Measurement and Fair Value of Financial Instruments - Fair Value of Financial Assets and Liabilities Measured on Recurring Basis (Detail) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Assets:
Total	$ 1,170,938	$ 769,956
Equity securities, at fair value	16,915	17,368
U.S. Treasury and U.S. government agencies
Assets:
Total	383,715	203,387
Mortgage-backed securities, multifamily
Assets:
Total	1,603	1,741
Asset-backed securities
Assets:
Total	62,956	52,584
Obligations of states and political subdivisions
Assets:
Total	23,478
Corporate bonds
Assets:
Total	94,469	50,459
Fair Value, Measurements, Recurring
Assets:
Total	1,170,938	769,956
Equity securities, at fair value	16,915	17,368
Derivative assets	47,473	43,799
Total Assets	1,235,326	831,123
Liabilities:
Derivative liabilities	47,473	43,799
Total Liabilities	47,473	43,799
Fair Value, Measurements, Recurring | U.S. Treasury and U.S. government agencies
Assets:
Total	383,715	203,387
Fair Value, Measurements, Recurring | Mortgage-backed securities, residential
Assets:
Total	360,696	237,975
Fair Value, Measurements, Recurring | Collateralized mortgage obligations, residential
Assets:
Total	189,790	191,291
Fair Value, Measurements, Recurring | Mortgage-backed securities, multifamily
Assets:
Total	1,603	1,741
Fair Value, Measurements, Recurring | Collateralized mortgage obligations, multifamily
Assets:
Total	54,231	32,519
Fair Value, Measurements, Recurring | Asset-backed securities
Assets:
Total	62,956	52,584
Fair Value, Measurements, Recurring | Obligations of states and political subdivisions
Assets:
Total	23,478
Fair Value, Measurements, Recurring | Corporate bonds
Assets:
Total	94,469	50,459
Quoted Prices in Active Markets for Identical Assets (Level 1) | Fair Value, Measurements, Recurring
Assets:
Total	170,404	104,861
Equity securities, at fair value	0	0
Derivative assets	0	0
Total Assets	170,404	104,861
Liabilities:
Derivative liabilities	0	0
Total Liabilities	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) | Fair Value, Measurements, Recurring | U.S. Treasury and U.S. government agencies
Assets:
Total	170,404	104,861
Quoted Prices in Active Markets for Identical Assets (Level 1) | Fair Value, Measurements, Recurring | Mortgage-backed securities, residential
Assets:
Total	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) | Fair Value, Measurements, Recurring | Collateralized mortgage obligations, residential
Assets:
Total	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) | Fair Value, Measurements, Recurring | Mortgage-backed securities, multifamily
Assets:
Total	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) | Fair Value, Measurements, Recurring | Collateralized mortgage obligations, multifamily
Assets:
Total	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) | Fair Value, Measurements, Recurring | Asset-backed securities
Assets:
Total	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) | Fair Value, Measurements, Recurring | Obligations of states and political subdivisions
Assets:
Total	0
Quoted Prices in Active Markets for Identical Assets (Level 1) | Fair Value, Measurements, Recurring | Corporate bonds
Assets:
Total	0	0
Significant Other Observable Inputs (Level 2) | Fair Value, Measurements, Recurring
Assets:
Total	1,000,534	665,095
Equity securities, at fair value	16,915	17,368
Derivative assets	47,473	43,799
Total Assets	1,064,922	726,262
Liabilities:
Derivative liabilities	47,473	43,799
Total Liabilities	47,473	43,799
Significant Other Observable Inputs (Level 2) | Fair Value, Measurements, Recurring | U.S. Treasury and U.S. government agencies
Assets:
Total	213,311	98,526
Significant Other Observable Inputs (Level 2) | Fair Value, Measurements, Recurring | Mortgage-backed securities, residential
Assets:
Total	360,696	237,975
Significant Other Observable Inputs (Level 2) | Fair Value, Measurements, Recurring | Collateralized mortgage obligations, residential
Assets:
Total	189,790	191,291
Significant Other Observable Inputs (Level 2) | Fair Value, Measurements, Recurring | Mortgage-backed securities, multifamily
Assets:
Total	1,603	1,741
Significant Other Observable Inputs (Level 2) | Fair Value, Measurements, Recurring | Collateralized mortgage obligations, multifamily
Assets:
Total	54,231	32,519
Significant Other Observable Inputs (Level 2) | Fair Value, Measurements, Recurring | Asset-backed securities
Assets:
Total	62,956	52,584
Significant Other Observable Inputs (Level 2) | Fair Value, Measurements, Recurring | Obligations of states and political subdivisions
Assets:
Total	23,478
Significant Other Observable Inputs (Level 2) | Fair Value, Measurements, Recurring | Corporate bonds
Assets:
Total	94,469	50,459
Significant Unobservable Inputs (Level 3) | Fair Value, Measurements, Recurring
Assets:
Total	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
Significant Unobservable Inputs (Level 3) | Fair Value, Measurements, Recurring | U.S. Treasury and U.S. government agencies
Assets:
Total	0	0
Significant Unobservable Inputs (Level 3) | Fair Value, Measurements, Recurring | Mortgage-backed securities, residential
Assets:
Total	0	0
Significant Unobservable Inputs (Level 3) | Fair Value, Measurements, Recurring | Collateralized mortgage obligations, residential
Assets:
Total	0	0
Significant Unobservable Inputs (Level 3) | Fair Value, Measurements, Recurring | Mortgage-backed securities, multifamily
Assets:
Total	0	0
Significant Unobservable Inputs (Level 3) | Fair Value, Measurements, Recurring | Collateralized mortgage obligations, multifamily
Assets:
Total	0	0
Significant Unobservable Inputs (Level 3) | Fair Value, Measurements, Recurring | Asset-backed securities
Assets:
Total	0	0
Significant Unobservable Inputs (Level 3) | Fair Value, Measurements, Recurring | Obligations of states and political subdivisions
Assets:
Total	0
Significant Unobservable Inputs (Level 3) | Fair Value, Measurements, Recurring | Corporate bonds
Assets:
Total	$ 0	$ 0