INVESTMENT SECURITIES - Schedule of Investment Securities Classified as Current and Long-Term (Details) - USD ($) $ in Millions	Mar. 31, 2025	Dec. 31, 2024
Investment Securities, Available-for-sale Amortized Cost to Fair Value
Amortized Cost	$ 19,425	$ 20,018
Gross Unrealized Gains	36	26
Gross Unrealized Losses	(1,163)	(1,409)
Fair Value	18,298	18,635
U.S. Treasury and agency obligations
Investment Securities, Available-for-sale Amortized Cost to Fair Value
Amortized Cost	3,058	3,336
Gross Unrealized Gains	2	1
Gross Unrealized Losses	(61)	(110)
Fair Value	2,999	3,227
Mortgage-backed securities
Investment Securities, Available-for-sale Amortized Cost to Fair Value
Amortized Cost	4,399	4,504
Gross Unrealized Gains	2	0
Gross Unrealized Losses	(428)	(509)
Fair Value	3,973	3,995
Tax-exempt municipal securities
Investment Securities, Available-for-sale Amortized Cost to Fair Value
Amortized Cost	521	548
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(24)	(22)
Fair Value	497	526
Residential
Investment Securities, Available-for-sale Amortized Cost to Fair Value
Amortized Cost	599	586
Gross Unrealized Gains	1	0
Gross Unrealized Losses	(55)	(64)
Fair Value	545	522
Commercial
Investment Securities, Available-for-sale Amortized Cost to Fair Value
Amortized Cost	1,226	1,290
Gross Unrealized Gains	1	1
Gross Unrealized Losses	(72)	(85)
Fair Value	1,155	1,206
Asset-backed securities
Investment Securities, Available-for-sale Amortized Cost to Fair Value
Amortized Cost	1,367	1,424
Gross Unrealized Gains	5	3
Gross Unrealized Losses	(18)	(24)
Fair Value	1,354	1,403
Corporate debt securities
Investment Securities, Available-for-sale Amortized Cost to Fair Value
Amortized Cost	8,255	8,330
Gross Unrealized Gains	25	21
Gross Unrealized Losses	(505)	(595)
Fair Value	$ 7,775	$ 7,756

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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