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Description of Business and Summary of Significant Accounting Policies - Additional Information (Detail) - USD ($) | 12 Months Ended
--- | ---
Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items] |  |  |
Days from origination after which mortgage loans are sold | 30 days |  |
Loan upon which a default of principal or interest has existed for a period | 90 days |  |
Accrued interest receivable | $ 39,400,000 | $ 30,600,000 |
Accrued Interest and reversed against interest income | $ 429,000 | 147,000 | $ 83,000
Intangible assets, Estimated useful lives | 5 years 9 months 18 days |  |
Advertising costs | $ 3,200,000 | $ 3,000,000.0 | $ 3,000,000.0
Revenue recognition, description of performance obligation | the Company offers various services to customers that generate revenue. Contract performance typically occurs in one year or less. |  |
Incremental cost of obtaining contract | true |  |
Revenue recognition, description of payment terms | Revenue is recognized when the transactions occur or as services are performed over primarily monthly or quarterly periods. Payment is typically received in the period the transactions occur, or in some cases, within 90 days of the service period. |  |
Delinquency period placed on nonaccrual status loan | 90 days |  |
Commercial loans are charged off deemed uncollectible period | 180 days |  |
Accounting Standards Update 2022-02 [Member] |  |  |
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items] |  |  |
Change in Accounting Principle, Accounting Standards Update, Adopted [true false] | false |  |
Change in Accounting Principle, Accounting Standards Update, Adoption Date | Jan. 01, 2023 |  |
Change in Accounting Principle, Accounting Standards Update, Immaterial Effect [true false] | true |  |
Accounting Standards Update 2023-02 [Member] |  |  |
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items] |  |  |
Change in Accounting Principle, Accounting Standards Update, Adopted [true false] | false |  |
Change in Accounting Principle, Accounting Standards Update, Adoption Date | Jan. 01, 2023 |  |
Change in Accounting Principle, Accounting Standards Update, Immaterial Effect [true false] | true |  |
Unfunded other tax credit (LIHTC) | $ 25,100,000 |  |
Amortization and other tax credit of NMTC | $ 6,000,000 |  |
U.S. Treasury or U.S. Government-sponsored Entities and Agencies [Member] |  |  |
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items] |  |  |
Percentage of available for sale securities held | 98.00% | 98.00% |
Core Deposit Intangibles [Member] |  |  |
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items] |  |  |
Intangible assets, Estimated useful lives | 5 years 10 months 24 days |  |
Core Deposit Intangibles [Member] | Minimum [Member] |  |  |
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items] |  |  |
Intangible assets, Estimated useful lives | 7 years |  |
Core Deposit Intangibles [Member] | Maximum [Member] |  |  |
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items] |  |  |
Intangible assets, Estimated useful lives | 10 years |  |
Customer Relationship Intangibles [Member] | Minimum [Member] |  |  |
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items] |  |  |
Intangible assets, Estimated useful lives | 3 years |  |
Customer Relationship Intangibles [Member] | Maximum [Member] |  |  |
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items] |  |  |
Intangible assets, Estimated useful lives | 18 years |  |

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