AVAILABLE-FOR-SALE DEBT SECURITIES AND EQUITY SECURITIES - Summary of Reconciliation of Available-for-Sale Debt Securities from Cost Basis to Fair Value (Details) - USD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022
Available-for-Sale Debt Securities
Amortized Cost	$ 2,403	$ 2,325
Gross Unrealized Gains	0	1
Gross Unrealized Losses	(21)	(34)
Estimated Fair Value	2,382	2,293
U.S. treasury securities
Available-for-Sale Debt Securities
Amortized Cost	430	415
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(3)	(5)
Estimated Fair Value	428	410
U.S. government agencies securities
Available-for-Sale Debt Securities
Amortized Cost	153	36
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(1)	0
Estimated Fair Value	152	35
Non-U.S. government securities
Available-for-Sale Debt Securities
Amortized Cost	10	34
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Estimated Fair Value	10	34
Certificates of deposit
Available-for-Sale Debt Securities
Amortized Cost	97	54
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Estimated Fair Value	97	54
Corporate debt securities
Available-for-Sale Debt Securities
Amortized Cost	1,351	1,452
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(17)	(26)
Estimated Fair Value	1,334	1,427
Residential mortgage and asset-backed securities
Available-for-Sale Debt Securities
Amortized Cost	362	335
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(1)	(3)
Estimated Fair Value	$ 361	$ 333

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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Amount, before tax, of unrealized loss 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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Amortized cost excluding accrued interest, after allowance for credit loss, of 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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