AVAILABLE-FOR-SALE DEBT SECURITIES AND EQUITY SECURITIES - Summary of Available-for-Sale Debt Securities at Estimated Fair Value (Details) - USD ($) $ in Millions	Mar. 31, 2023	Dec. 31, 2022
Available-for-Sale Debt Securities
Amortized Cost	$ 2,350	$ 2,325
Gross Unrealized Gains	2	1
Gross Unrealized Losses	(26)	(34)
Estimated Fair Value	2,326	2,293
U.S. treasury securities
Available-for-Sale Debt Securities
Amortized Cost	346	415
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(2)	(5)
Estimated Fair Value	344	410
U.S. government agencies securities
Available-for-Sale Debt Securities
Amortized Cost	156	36
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Estimated Fair Value	155	35
Non-U.S. government securities
Available-for-Sale Debt Securities
Amortized Cost	23	34
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Estimated Fair Value	23	34
Certificates of deposit
Available-for-Sale Debt Securities
Amortized Cost	90	54
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Estimated Fair Value	90	54
Corporate debt securities
Available-for-Sale Debt Securities
Amortized Cost	1,400	1,452
Gross Unrealized Gains	1	0
Gross Unrealized Losses	(21)	(26)
Estimated Fair Value	1,379	1,427
Residential mortgage and asset-backed securities
Available-for-Sale Debt Securities
Amortized Cost	336	335
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(2)	(3)
Estimated Fair Value	$ 335	$ 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).

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=126970911&loc=d3e27161-111563

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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).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI https://asc.fasb.org/extlink&oid=126970911&loc=d3e27161-111563

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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).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 45
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=124258926&loc=SL82898722-210454

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Amount excluding accrued interest, 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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