Regulatory Matters - Schedule of Regulatory Capital Ratios Under the Basel III Regulatory Capital Framework (Detail) $ in Thousands	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
Compliance With Regulatory Capital Requirements Under Banking Regulations [Line Items]
Total Capital to Risk-Weighted Assets, Actual Ratio	0.1929	0.2034
Tier1 Capital to Risk-Weighted Assets, Actual Ratio	0.1822	0.1935
Common Equity Tier1 Capital to Risk-Weighted Assets, Actual Ratio	0.1822	0.1935
Leverage Ratio, Actual Ratio	0.1096	0.1113
Consolidated [Member]
Compliance With Regulatory Capital Requirements Under Banking Regulations [Line Items]
Total Capital to Risk-Weighted Assets, Actual Amount	$ 1,586,888	$ 1,425,907
Tier1 Capital to Risk-Weighted Assets, Actual Amount	1,498,731	1,356,006
Common Equity Tier1 Capital to Risk-Weighted Assets, Actual Amount	1,498,731	1,356,006
Leverage Ratio, Actual Amount	$ 1,498,731	$ 1,356,006
Total Capital to Risk-Weighted Assets, Actual Ratio	0.1929	0.2034
Tier1 Capital to Risk-Weighted Assets, Actual Ratio	0.1822	0.1935
Common Equity Tier1 Capital to Risk-Weighted Assets, Actual Ratio	0.1822	0.1935
Leverage Ratio, Actual Ratio	0.1096	0.1113
Consolidated [Member] | Minimum [Member]
Compliance With Regulatory Capital Requirements Under Banking Regulations [Line Items]
Total Capital to Risk-Weighted Assets, Required To Be Considered Well Capitalized, Amount	$ 822,497	$ 700,955
Tier1 Capital to Risk-Weighted Assets, Required To Be Considered Well Capitalized, Amount	$ 493,498	$ 420,573
Total Capital to Risk-Weighted Assets, Required To Be Considered Well Capitalized , Ratio	0.1000	0.1000
Tier1 Capital to Risk-Weighted Assets, Required To Be Considered Well Capitalized , Ratio	0.0600	0.0600
Consolidated [Member] | Minimum [Member] | Basel III Fully Phased-In [Member]
Compliance With Regulatory Capital Requirements Under Banking Regulations [Line Items]
Total Capital to Risk-Weighted Assets, Minimum Capital Required	$ 863,622	$ 736,003
Tier1 Capital to Risk-Weighted Assets, Minimum Capital Required	699,122	595,812
Common Equity Tier1 Capital to Risk-Weighted Assets, Minimum Capital Required	575,748	490,669
Leverage Ratio, Minimum Capital Required	$ 546,983	$ 487,459
Total Capital to Risk-Weighted Assets, Minimum Capital Required	0.1050	0.1050
Tier1 Capital to Risk-Weighted Assets, Minimum Capital Required	0.0850	0.0850
Common Equity Tier1 Capital to Risk-Weighted Assets, Minimum Capital Required, Ratio	0.0700	0.0700
Leverage Ratio, Minimum Capital Required, Ratio	0.0400	0.0400
Parent Company [Member]
Compliance With Regulatory Capital Requirements Under Banking Regulations [Line Items]
Total Capital to Risk-Weighted Assets, Actual Amount	$ 1,442,902	$ 1,258,965
Tier1 Capital to Risk-Weighted Assets, Actual Amount	1,354,745	1,189,064
Common Equity Tier1 Capital to Risk-Weighted Assets, Actual Amount	1,354,745	1,189,064
Leverage Ratio, Actual Amount	$ 1,354,745	$ 1,189,064
Total Capital to Risk-Weighted Assets, Actual Ratio	0.1758	0.1799
Tier1 Capital to Risk-Weighted Assets, Actual Ratio	0.1650	0.1700
Common Equity Tier1 Capital to Risk-Weighted Assets, Actual Ratio	0.1650	0.1700
Leverage Ratio, Actual Ratio	0.0995	0.0979
Parent Company [Member] | Minimum [Member]
Compliance With Regulatory Capital Requirements Under Banking Regulations [Line Items]
Total Capital to Risk-Weighted Assets, Required To Be Considered Well Capitalized, Amount	$ 820,819	$ 699,623
Tier1 Capital to Risk-Weighted Assets, Required To Be Considered Well Capitalized, Amount	656,655	559,698
Common Equity Tier1 Capital to Risk-Weighted Assets, Required To Be Considered Well Capitalized, Amount	533,532	454,755
Leverage Ratio, Required To Be Considered Well Capitalized, Amount	$ 681,107	$ 607,407
Total Capital to Risk-Weighted Assets, Required To Be Considered Well Capitalized , Ratio	0.1000	0.1000
Tier1 Capital to Risk-Weighted Assets, Required To Be Considered Well Capitalized , Ratio	0.0800	0.0800
Common Equity Tier1 Capital to Risk-Weighted Assets, Required To Be Considered Well Capitalized , Ratio	0.0650	0.0650
Leverage Ratio, Required To Be Considered Well Capitalized , Ratio	0.0500	0.0500
Parent Company [Member] | Minimum [Member] | Basel III Fully Phased-In [Member]
Compliance With Regulatory Capital Requirements Under Banking Regulations [Line Items]
Total Capital to Risk-Weighted Assets, Minimum Capital Required	$ 861,860	$ 734,604
Tier1 Capital to Risk-Weighted Assets, Minimum Capital Required	697,696	594,679
Common Equity Tier1 Capital to Risk-Weighted Assets, Minimum Capital Required	574,573	489,736
Leverage Ratio, Minimum Capital Required	$ 544,886	$ 485,926
Total Capital to Risk-Weighted Assets, Minimum Capital Required	0.1050	0.1050
Tier1 Capital to Risk-Weighted Assets, Minimum Capital Required	0.0850	0.0850
Common Equity Tier1 Capital to Risk-Weighted Assets, Minimum Capital Required, Ratio	0.0700	0.0700
Leverage Ratio, Minimum Capital Required, Ratio	0.0400	0.0400