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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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Amount of operating interest income, including amortization and accretion of premiums and discounts, on held-to-maturity securities.

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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.

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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

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Investment Income, Debt Securities Excluding Trading Securities, Operating

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