AVAILABLE-FOR-SALE DEBT SECURITIES AND EQUITY SECURITIES - Summary of Reconciliation of Available-for-Sale Debt Securities from Cost Basis to Fair Value (Details) $ in Millions	Dec. 31, 2023 USD ($)
Available-for-Sale Debt Securities
Amortized Cost	$ 2,430
Gross Unrealized Gains	5
Gross Unrealized Losses	(10)
Estimated Fair Value	2,426
U.S. treasury securities
Available-for-Sale Debt Securities
Amortized Cost	427
Gross Unrealized Gains	0
Gross Unrealized Losses	(1)
Estimated Fair Value	426
U.S. government agencies securities
Available-for-Sale Debt Securities
Amortized Cost	127
Gross Unrealized Gains	0
Gross Unrealized Losses	0
Estimated Fair Value	127
Non-U.S. government securities
Available-for-Sale Debt Securities
Amortized Cost	10
Gross Unrealized Gains	0
Gross Unrealized Losses	0
Estimated Fair Value	10
Certificates of deposit
Available-for-Sale Debt Securities
Amortized Cost	45
Gross Unrealized Gains	0
Gross Unrealized Losses	0
Estimated Fair Value	45
Corporate debt securities
Available-for-Sale Debt Securities
Amortized Cost	1,455
Gross Unrealized Gains	4
Gross Unrealized Losses	(8)
Estimated Fair Value	1,451
Residential mortgage and asset-backed securities
Available-for-Sale Debt Securities
Amortized Cost	366
Gross Unrealized Gains	1
Gross Unrealized Losses	0
Estimated Fair Value	$ 367

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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