INVESTMENT SECURITIES - Schedule of Amortized Cost and Fair Value of Investment Securities (Details) - USD ($) $ in Millions	Mar. 31, 2025	Dec. 31, 2024
Investment securities available for sale
Amortized Cost	$ 34,340	$ 34,512
Gross Unrealized Gains	220	81
Gross Unrealized Losses	(660)	(843)
Investment securities available for sale	33,900	33,750
Investment in marketable equity securities
Amortized Cost	78	79
Gross Unrealized Gains	21	27
Gross Unrealized Losses	(4)	(5)
Fair Value	95	101
Investment securities held to maturity
Amortized Cost	10,324	10,239
Gross Unrealized Gains	17	2
Gross Unrealized Losses	(1,368)	(1,539)
Fair Value	8,973	8,702
Total investment securities
Amortized Cost	44,742	44,830
Gross Unrealized Gains	258	110
Gross Unrealized Losses	(2,032)	(2,387)
Fair Value	42,968	42,553
U.S. Treasury
Investment securities available for sale
Amortized Cost	13,105	13,897
Gross Unrealized Gains	55	33
Gross Unrealized Losses	(10)	(27)
Investment securities available for sale	13,150	13,903
Investment securities held to maturity
Amortized Cost	484	483
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(25)	(31)
Fair Value	459	452
Government agency
Investment securities available for sale
Amortized Cost	71	79
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(2)	(2)
Investment securities available for sale	69	77
Investment securities held to maturity
Amortized Cost	1,491	1,489
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(91)	(115)
Fair Value	1,400	1,374
Residential mortgage-backed securities
Investment securities available for sale
Amortized Cost	16,905	16,161
Gross Unrealized Gains	143	41
Gross Unrealized Losses	(443)	(582)
Investment securities available for sale	16,605	15,620
Investment securities held to maturity
Amortized Cost	4,668	4,558
Gross Unrealized Gains	17	2
Gross Unrealized Losses	(595)	(682)
Fair Value	4,090	3,878
Commercial mortgage-backed securities
Investment securities available for sale
Amortized Cost	3,759	3,869
Gross Unrealized Gains	21	7
Gross Unrealized Losses	(186)	(210)
Investment securities available for sale	3,594	3,666
Investment securities held to maturity
Amortized Cost	3,378	3,407
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(630)	(678)
Fair Value	2,748	2,729
Corporate bonds
Investment securities available for sale
Amortized Cost	483	489
Gross Unrealized Gains	1	0
Gross Unrealized Losses	(19)	(22)
Investment securities available for sale	465	467
Municipal bonds
Investment securities available for sale
Amortized Cost	17	17
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Investment securities available for sale	17	17
Supranational securities
Investment securities held to maturity
Amortized Cost	301	300
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(27)	(33)
Fair Value	274	267
Other
Investment securities held to maturity
Amortized Cost	2	2
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Fair Value	$ 2	$ 2

Equity Securities FV-NI, Accumulated Gross Unrealized Gain, before Tax

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