INVESTMENT SECURITIES - Schedule of Aggregate Amount of Unrealized Losses on Debt Securities in AFS Investment Portfolios (Details) - USD ($) $ in Millions	Sep. 30, 2026	Dec. 31, 2025
Fair Value
Less than 12 months	$ 3,665	$ 459
12 months or longer	4,343	4,719
Unrealized Losses
Less than 12 months	(68)	(1)
12 months or longer	$ (871)	$ (687)
FDIC \| Structured LLC
Unrealized Losses
Equity ownership, excluding consolidated entity and equity method investee, percentage	20.00%	20.00%
U.S. Treasury securities
Fair Value
Less than 12 months	$ 226	$ 0
12 months or longer	0	0
Unrealized Losses
Less than 12 months	(1)	0
12 months or longer	0	0
Corporate and other securities
Fair Value
Less than 12 months	9	0
12 months or longer	0	0
Unrealized Losses
Less than 12 months	0	0
12 months or longer	0	0
ABS
Fair Value
Less than 12 months	946	434
12 months or longer	369	190
Unrealized Losses
Less than 12 months	(2)	(1)
12 months or longer	(2)	(2)
Beneficial Interest in Structured LLC
Fair Value
Less than 12 months	977	0
12 months or longer	0	0
Unrealized Losses
Less than 12 months	(30)	0
12 months or longer	0	0
GNMA - Residential
Fair Value
Less than 12 months	1,262	25
12 months or longer	2,035	2,346
Unrealized Losses
Less than 12 months	(29)	0
12 months or longer	(352)	(254)
GNMA - Commercial
Fair Value
Less than 12 months	0	0
12 months or longer	437	479
Unrealized Losses
Less than 12 months	0	0
12 months or longer	(163)	(143)
FHLMC and FNMA - Residential
Fair Value
Less than 12 months	245	0
12 months or longer	1,426	1,623
Unrealized Losses
Less than 12 months	(6)	0
12 months or longer	(352)	(288)
FHLMC and FNMA - Commercial
Fair Value
Less than 12 months	0	0
12 months or longer	76	81
Unrealized Losses
Less than 12 months	0	0
12 months or longer	$ (2)	$ 0

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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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Amount of accumulated unrealized loss on 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 12 months or longer, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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Percentage of ownership of equity interest excluding interest in entity that is consolidated and equity method investee.

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