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Investment Securities - Summary of Carrying Value of Available-for-Sale Securities (Details) - USD ($) $ in Thousands | Dec. 31, 2025 | Dec. 31, 2024
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Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items] |  |
Total available-for-sale securities pledged | $ 9,439,503 | $ 8,459,561
Pledged for deposits |  |
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items] |  |
Total available-for-sale securities pledged | 1,779,781 | 1,596,378
Pledged for borrowings and other |  |
Debt Securities, Held-to-maturity, Allowance for Credit Loss [Line Items] |  |
Total available-for-sale securities pledged | $ 7,659,722 | $ 6,863,183

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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 Available-for-sale or Held-for-investment + References No definition available. + Details
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