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, 2021	Dec. 31, 2020
Assets:
Fair Value	$ 769,956	$ 855,746
Equity securities, at fair value	17,368	14,694
Fair Value, Measurements, Recurring
Assets:
Fair Value	769,956	855,746
Equity securities, at fair value	17,368	14,694
Derivative assets	43,799	80,734
Total Assets	831,123	951,174
Liabilities:
Derivative liabilities	43,799	80,877
Total Liabilities	43,799	80,877
Quoted Prices in Active Markets for Identical Assets (Level 1) \| Fair Value, Measurements, Recurring
Assets:
Fair Value	104,861	9,392
Equity securities, at fair value	0	0
Derivative assets	0	0
Total Assets	104,861	9,392
Liabilities:
Derivative liabilities	0	0
Total Liabilities	0	0
Significant Other Observable Inputs (Level 2) \| Fair Value, Measurements, Recurring
Assets:
Fair Value	665,095	846,354
Equity securities, at fair value	17,368	14,694
Derivative assets	43,799	80,734
Total Assets	726,262	941,782
Liabilities:
Derivative liabilities	43,799	80,877
Total Liabilities	43,799	80,877
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	203,387	65,002
U.S. Treasury and U.S. government agencies \| Fair Value, Measurements, Recurring
Assets:
Fair Value	203,387	65,002
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	104,861	9,392
U.S. Treasury and U.S. government agencies \| Significant Other Observable Inputs (Level 2) \| Fair Value, Measurements, Recurring
Assets:
Fair Value	98,526	55,610
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	237,975	228,156
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	237,975	228,156
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	191,291	209,038
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	191,291	209,038
Collateralized mortgage obligations, residential \| Significant Unobservable Inputs (Level 3) \| Fair Value, Measurements, Recurring
Assets:
Fair Value	0	0
Mortgage-backed securities, multifamily \| Fair Value, Measurements, Recurring
Assets:
Fair Value	1,741	1,944
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	1,741	1,944
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	32,519	41,535
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	32,519	41,535
Collateralized mortgage obligations, multifamily \| Significant Unobservable Inputs (Level 3) \| Fair Value, Measurements, Recurring
Assets:
Fair Value	0	0
Asset-backed securities
Assets:
Fair Value	52,584	40,690
Asset-backed securities \| Fair Value, Measurements, Recurring
Assets:
Fair Value	52,584	40,690
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	52,584	40,690
Asset-backed securities \| Significant Unobservable Inputs (Level 3) \| Fair Value, Measurements, Recurring
Assets:
Fair Value	0	0
Corporate debt securities \| Fair Value, Measurements, Recurring
Assets:
Fair Value	50,459	35,671
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	50,459	35,671
Corporate debt securities \| Significant Unobservable Inputs (Level 3) \| Fair Value, Measurements, Recurring
Assets:
Fair Value	$ 0	0
Obligations of states and political subdivisions
Assets:
Fair Value		233,710
Obligations of states and political subdivisions \| Fair Value, Measurements, Recurring
Assets:
Fair Value		233,710
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		233,710
Obligations of states and political subdivisions \| Significant Unobservable Inputs (Level 3) \| Fair Value, Measurements, Recurring
Assets:
Fair Value		$ 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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