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INVESTMENT SECURITIES (Schedule of Investment Securities, Taxable and Nontaxable) (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2025 | Sep. 30, 2024
Net Investment Income [Line Items] |  |  |  |
Available-for-sale | $ 73 | $ 83 | $ 217 | $ 251
Held-to-maturity | 51 | 55 | 155 | 168
Interest on securities | 124 | 138 | 372 | 419
Taxable |  |  |  |
Net Investment Income [Line Items] |  |  |  |
Available-for-sale | 66 | 75 | 196 | 227
Held-to-maturity | 49 | 54 | 151 | 165
Interest on securities | 115 | 129 | 347 | 392
Nontaxable |  |  |  |
Net Investment Income [Line Items] |  |  |  |
Available-for-sale | 7 | 8 | 21 | 24
Held-to-maturity | 2 | 1 | 4 | 3
Interest on securities | $ 9 | $ 9 | $ 25 | $ 27

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- Definition Amount of interest income, amortization of premium and accretion of discount on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale); classified as operating. + References No definition available. + 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/2003/role/disclosureRef -Topic 944 -SubTopic 220 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04(2)(a)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147477250/944-220-S99-1 + Details
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