Investment Securities - Additional Information (Detail) - USD ($) $ in Thousands |
9 Months Ended | |
|---|---|---|
Sep. 30, 2026 |
Dec. 31, 2025 |
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| Debt Securities, Available-for-sale [Line Items] | ||
| Allowance for credit loss | $ 0 | $ 0 |
| Debt securities weighted average remaining contractual maturity term | 25 years | |
| Total deposits | $ 15,730,179 | 12,071,982 |
| Investment in FHLB stock, impairment losses | 0 | |
| Gross unrealized holding losses of available-for-sale securities | 23,600 | |
| Investment Securities-AFS [Member] | ||
| Debt Securities, Available-for-sale [Line Items] | ||
| Pledged to secure amount | 2,680,000 | 2,740,000 |
| Total deposits | 1,020,000 | 942,000 |
| Secure public funds | 682,300 | 548,600 |
| Secured unused borrowing capacity | 1,870,000 | 1,350,000 |
| Other purposes | 70,100 | 57,000 |
| Pledged to secure unused borrowing capacity | $ 2,620,000 | $ 2,000,000 |
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- Definition Accumulated Other Comprehensive Income (Loss), Other than Temporary Impairment, Not Credit Loss, Net of Tax, Available-for-Sale, Debt Securitie No definition available.
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- Definition Debt securities weighted average remaining contractual maturity term. No definition available.
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- Definition Investment securities for other purposes No definition available.
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- Definition Pledged to secure No definition available.
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- Definition Pledged To Secure Unused Borrowing Capacity No definition available.
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- Definition Secure Public Funds No definition available.
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- Definition Amount of unused borrowing capacity under the long-term financing arrangement that is available to the entity as of the balance sheet date. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount, before tax, of unrealized gain (loss) in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount of allowance for credit loss for debt security measured at amortized cost (held-to-maturity). Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition The aggregate of all deposit liabilities held by the entity, including foreign and domestic, interest and noninterest bearing; may include demand deposits, saving deposits, Negotiable Order of Withdrawal (NOW) and time deposits among others. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Details
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