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Description of Business and Summary of Significant Accounting Policies - Additional Information (Detail) - USD ($) | 12 Months Ended
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Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020
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 | $ 30,600,000 | $ 21,000,000.0 |
Accrued Interest and reversed against interest income | $ 147,000 | 83,000 | $ 841,000,000,000
Intangible assets, Estimated useful lives | 6 years 7 months 6 days |  |
Advertising costs | $ 3,000,000.0 | 3,000,000.0 | 3,300,000
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 |  |
Paycheck Protection Program, CARES Act [Member] | Small Business Administration (SBA) [Member] |  |  |
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items] |  |  |
Percentage of processing fees | 5.00% |  |
Unamortized balances of fees | $ 0 | 2,000,000.0 |
Processing fees received from the SBA |  | $ 23,800,000 | $ 30,200,000
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 | 6 years 8 months 12 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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