INVESTMENT SECURITIES - Schedule of Aggregate Amount of Unrealized Losses on Debt Securities in HTM Investment Portfolios (Details) - USD ($) $ in Millions	Sep. 30, 2026	Dec. 31, 2025
Fair Value
Less than 12 months	$ 10,671	$ 731
12 months or longer	5,835	6,494
Unrealized Losses
Less than 12 months	(321)	(3)
12 months or longer	(1,669)	(1,366)
U.S. Treasury securities
Fair Value
Less than 12 months	1,771	305
12 months or longer	0	0
Unrealized Losses
Less than 12 months	(17)	0
12 months or longer	0	0
ABS and other interests in structured securities
Fair Value
Less than 12 months	911	262
12 months or longer	35	5
Unrealized Losses
Less than 12 months	(14)	(2)
12 months or longer	(1)	0
GNMA - Residential
Fair Value
Less than 12 months	2,043	74
12 months or longer	1,637	1,858
Unrealized Losses
Less than 12 months	(41)	0
12 months or longer	(490)	(402)
GNMA - Commercial
Fair Value
Less than 12 months	2,658	21
12 months or longer	3,256	3,588
Unrealized Losses
Less than 12 months	(128)	(1)
12 months or longer	(1,053)	(887)
FHLMC and FNMA - Residential
Fair Value
Less than 12 months	2,442	22
12 months or longer	907	1,043
Unrealized Losses
Less than 12 months	(90)	0
12 months or longer	(125)	(77)
FHLMC and FNMA - Commercial
Fair Value
Less than 12 months	846	47
12 months or longer	0	0
Unrealized Losses
Less than 12 months	(31)	0
12 months or longer	$ 0	$ 0

Amount of accumulated unrealized loss on investment in debt security measured at amortized cost (held-to-maturity), in continuous loss position for 12 months or longer.

Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 7
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-7

Reference 2: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Topic 320
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-Section 50
-Paragraph 6
-Subparagraph (a)(2)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-6

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