AVAILABLE-FOR-SALE DEBT SECURITIES AND EQUITY SECURITIES - Summary of Available-for-Sale Debt Securities at Estimated Fair Value (Details) - USD ($) $ in Millions	Jun. 30, 2023	Dec. 31, 2022
Available-for-Sale Debt Securities
Amortized Cost	$ 2,367	$ 2,325
Gross Unrealized Gains	0	1
Gross Unrealized Losses	(26)	(34)
Estimated Fair Value	2,341	2,293
U.S. treasury securities
Available-for-Sale Debt Securities
Amortized Cost	378	415
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(3)	(5)
Estimated Fair Value	375	410
U.S. government agencies securities
Available-for-Sale Debt Securities
Amortized Cost	162	36
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(1)	0
Estimated Fair Value	161	35
Non-U.S. government securities
Available-for-Sale Debt Securities
Amortized Cost	16	34
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Estimated Fair Value	15	34
Certificates of deposit
Available-for-Sale Debt Securities
Amortized Cost	104	54
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Estimated Fair Value	104	54
Corporate debt securities
Available-for-Sale Debt Securities
Amortized Cost	1,358	1,452
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(20)	(26)
Estimated Fair Value	1,338	1,427
Residential mortgage and asset-backed securities
Available-for-Sale Debt Securities
Amortized Cost	348	335
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(2)	(3)
Estimated Fair Value	$ 346	$ 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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