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Investment Securities - Additional Information (Detail) $ in Thousands | 12 Months Ended |
--- | --- | ---
Dec. 31, 2024 USD ($) Security shares | Dec. 31, 2023 USD ($) | Dec. 31, 2022 USD ($) | Oct. 31, 2021 USD ($)
Debt Securities, Available-for-sale [Line Items] |  |  |  |  |
Securities available for sale |  | $ 1,147,623 | $ 1,020,986 |  |
Other investments |  | $ 25,200 | 44,700 |  |
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions | Security |  | 175 |  |  |
Equity Securities, FV-NI, Gain (Loss) |  | $ 5,664 | 0 | $ 0 |
Total debt securities, Amortized Cost |  | 1,267,747 | 1,138,425 |  |
Debt Securities, Available-for-Sale |  | $ 1,147,623 | 1,020,986 |  |
Expected Class B2 Shares | shares |  | 13,340 |  |  |
Expected Class C Visa Shares | shares |  | 5,294 |  |  |
Equity Securities Fv Ni Gain Loss Subsequent to Year End |  | $ 5,100 |  |  |
Other Investments and Securities, at Cost |  | 5,700 | 6,200 |  |
Gain (Loss) on Sale of Other Investments |  | 0 | 0 |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings On Assets Held At Year End |  | 0 | 0 |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Transfers Between Levels 1 And 2 |  | 0 |  |  |
Corporate securities transferred from Level 3 to Level 2 |  |  | 0 |  |
2021 Share Repurchase Plan 2 |  |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |  |
Announcement of common stock repurchase program |  |  |  |  | $ 25,000
Obligations of U.S. Government-Sponsored Enterprises [Member] |  |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |  |
Securities available for sale |  | 350,600 |  |  |
Total debt securities, Amortized Cost | [1] | 413,400 |  |  |
Debt Securities, Available-for-Sale |  | 350,600 |  |  |
Held-to-maturity Securities [Member] |  |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |  |
Deposit Liabilities, Collateral Issued, Financial Instruments |  | 247,500 | 98,100 |  |
Available-for-sale Securities [Member] |  |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |  |
Deposit Liabilities, Collateral Issued, Financial Instruments |  | 580,500 | 386,500 |  |
Mortgage - Backed Securities - Residential [Member] | Obligations of U.S. Government-Sponsored Enterprises [Member] |  |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |  |
Securities available for sale |  | 350,584 | 494,599 |  |
Total debt securities, Amortized Cost |  | 413,434 | 559,769 |  |
Debt Securities, Available-for-Sale |  | 350,584 | 494,599 |  |
Corporate Securities [Member] |  |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |  |
Securities available for sale |  | 61,493 | 48,412 |  |
Total debt securities, Amortized Cost |  | 62,475 | 51,886 |  |
Debt Securities, Available-for-Sale |  | 61,493 | 48,412 |  |
Sales [Member] |  |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |  |
Gross Gains |  | 0 | 0 | 0 |
Calls And Maturities [Member] |  |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |  |
Gross Gains |  | 89 | $ 0 | $ 2 |
Sold Subsequent to Year End |  |  |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |  |  |
Securities available for sale |  | 75,100 |  |  |
Debt Securities, Available-for-Sale |  | $ 75,100 |  |  |
[1] | Mortgage Backed Securities include an amortized cost of $782.3 million and a fair value of $727.1 million for Obligations of U.S. Government agencies issued by Ginnie Mae and an amortized cost of $413.4 million and a fair value of $350.6 million for Obligations of U.S. Government-sponsored enterprises issued by Fannie Mae and Freddie Mac.

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