INVESTMENT SECURITIES - Securities Classified as Current and Long-Term (Details) - USD ($) $ in Millions	Mar. 31, 2023	Dec. 31, 2022
Investment Securities, Available-for-sale Amortized Cost to Fair Value
Amortized Cost	$ 16,747	$ 15,946
Gross Unrealized Gains	35	9
Gross Unrealized Losses	(1,479)	(1,701)
Fair Value	15,303	14,254
Common stock	0	7
Total investment securities	15,303	14,261
U.S. Treasury and agency obligations
Investment Securities, Available-for-sale Amortized Cost to Fair Value
Amortized Cost	1,394	1,093
Gross Unrealized Gains	9	1
Gross Unrealized Losses	(47)	(55)
Fair Value	1,356	1,039
Mortgage-backed securities
Investment Securities, Available-for-sale Amortized Cost to Fair Value
Amortized Cost	3,919	3,697
Gross Unrealized Gains	7	4
Gross Unrealized Losses	(423)	(471)
Fair Value	3,503	3,230
Tax-exempt municipal securities
Investment Securities, Available-for-sale Amortized Cost to Fair Value
Amortized Cost	762	765
Gross Unrealized Gains	1	0
Gross Unrealized Losses	(27)	(37)
Fair Value	736	728
Residential
Investment Securities, Available-for-sale Amortized Cost to Fair Value
Amortized Cost	470	477
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(73)	(76)
Fair Value	397	401
Commercial
Investment Securities, Available-for-sale Amortized Cost to Fair Value
Amortized Cost	1,562	1,554
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(149)	(155)
Fair Value	1,413	1,399
Asset-backed securities
Investment Securities, Available-for-sale Amortized Cost to Fair Value
Amortized Cost	1,915	1,809
Gross Unrealized Gains	2	1
Gross Unrealized Losses	(64)	(79)
Fair Value	1,853	1,731
Corporate debt securities
Investment Securities, Available-for-sale Amortized Cost to Fair Value
Amortized Cost	6,725	6,551
Gross Unrealized Gains	16	3
Gross Unrealized Losses	(696)	(828)
Fair Value	$ 6,045	$ 5,726

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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