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Investment Securities - Narrative (Detail) - USD ($) | 12 Months Ended |
--- | --- | ---
Dec. 31, 2025 | Dec. 31, 2024
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items] |  |
Increase (decrease) in gross unrealized losses | $ (176,900,000) |
Investment securities available-for-sale, at fair value | 0 | $ 867,000
Securities held-to-maturity | 0 | 0
Corporate debt |  |
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items] |  |
Investment securities available-for-sale, at fair value | $ 0 | $ 867,000

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- Definition Amount excluding accrued interest, of allowance for credit loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 30 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479130/326-30-45-1 + Details
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- Definition Amount excluding accrued interest, of investment in debt security measured at amortized cost (held-to-maturity) on nonaccrual status. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 16 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479319/326-20-50-16 + Details
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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. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 13 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479319/326-20-50-13 + Details
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- Definition Debt Securities, Available-for-Sale, Increase (Decrease) in Unrealized Losses + References No definition available. + Details
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