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Investment Securities - Summary of Carrying Value of Held-to-Maturity Securities (Detail) - USD ($) $ in Thousands | Dec. 31, 2024 | Dec. 31, 2023
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Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items] |  |
Total held-to-maturity securities pledged | $ 8,237,273 | $ 6,795,203
Pledged for deposits |  |
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items] |  |
Total held-to-maturity securities pledged | 1,978,445 | 1,212,824
Pledged for borrowings and other |  |
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items] |  |
Total held-to-maturity securities pledged | $ 6,258,828 | $ 5,582,379

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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 Pledged Financial Instruments, Not Separately Reported, Debt Securities Held-to-Maturity + References No definition available. + Details
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