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INVESTMENT SECURITIES - Schedule of Securities Pledged as Collateral (Details) - USD ($) $ in Millions | Dec. 31, 2025 | Dec. 31, 2024
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Investments, Debt and Equity Securities [Abstract] |  |
Securities pledged (carrying value), to secure public deposits, trust deposits and for other purposes as required by law | $ 6,445 | $ 6,271
Securities pledged (carrying value), as collateral for short-term borrowings | $ 140 | $ 182
Securities pledged as a percent of total securities | 84.00% | 86.70%

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- Definition Percentage as of the balance sheet date of securities that had been pledged for various purposes. + References No definition available. + Details
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- Definition The carrying amount (fair value) as of the balance sheet date of securities held that had been pledged to secure public deposits, trust deposits and for other purposes as required by law. + References No definition available. + Details
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- Definition The carrying amount (fair value) as of the balance sheet date of securities held that had been pledged by counterparties under financing and lending arrangements, pursuant to which the entity has the right by agreement or custom to sell or re-pledge such securities. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 5 -Publisher FASB -URI https://asc.fasb.org/1943274/2147481962/310-10-50-5 + Details
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