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Investment Securities - Summary of Carrying Value of Available-for-Sale Securities (Details) - 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 available-for-sale securities pledged | $ 8,459,561 | $ 8,213,545
Pledged for deposits |  |
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items] |  |
Total available-for-sale securities pledged | 1,596,378 | 2,102,115
Pledged for borrowings and other |  |
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items] |  |
Total available-for-sale securities pledged | $ 6,863,183 | $ 6,111,430

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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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