INVESTMENT SECURITIES (Summary of Amount of Gross Unrealized Losses for Debt Securities and Estimated Fair Value) (Details) - USD ($) $ in Millions	Dec. 31, 2025	Dec. 31, 2024
Gross unrealized losses
Available-for-sale, Less than 12 months	$ 2	$ 3
Available-for-sale, 12 months or more	1,166	1,504
Available-for-sale, Total	1,168	1,507
Estimated fair value
Available-for-sale, less than 12 Months	299	390
Available-for-sale, 12 months or more	7,425	8,230
Available-for-sale, Total	7,724	8,620
U.S. Treasury securities
Gross unrealized losses
Available-for-sale, Less than 12 months	0	3
Available-for-sale, 12 months or more	106	116
Available-for-sale, Total	106	119
Estimated fair value
Available-for-sale, less than 12 Months	99	198
Available-for-sale, 12 months or more	296	285
Available-for-sale, Total	395	483
Agency securities
Gross unrealized losses
Available-for-sale, Less than 12 months	0	0
Available-for-sale, 12 months or more	15	26
Available-for-sale, Total	15	26
Estimated fair value
Available-for-sale, less than 12 Months	7	3
Available-for-sale, 12 months or more	288	403
Available-for-sale, Total	295	406
Agency guaranteed mortgage-backed securities
Gross unrealized losses
Available-for-sale, Less than 12 months	2	0
Available-for-sale, 12 months or more	987	1,263
Available-for-sale, Total	989	1,263
Estimated fair value
Available-for-sale, less than 12 Months	86	86
Available-for-sale, 12 months or more	5,735	6,171
Available-for-sale, Total	5,821	6,257
Small Business Administration loan-backed securities
Gross unrealized losses
Available-for-sale, Less than 12 months	0	0
Available-for-sale, 12 months or more	14	21
Available-for-sale, Total	14	21
Estimated fair value
Available-for-sale, less than 12 Months	24	35
Available-for-sale, 12 months or more	309	387
Available-for-sale, Total	333	422
Municipal securities
Gross unrealized losses
Available-for-sale, Less than 12 months	0	0
Available-for-sale, 12 months or more	44	78
Available-for-sale, Total	44	78
Estimated fair value
Available-for-sale, less than 12 Months	68	68
Available-for-sale, 12 months or more	797	984
Available-for-sale, Total	865	$ 1,052
Other
Gross unrealized losses
Available-for-sale, Less than 12 months	0
Available-for-sale, 12 months or more	0
Available-for-sale, Total	0
Estimated fair value
Available-for-sale, less than 12 Months	15
Available-for-sale, 12 months or more	0
Available-for-sale, Total	$ 15

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for more than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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