FAIR VALUE MEASUREMENTS - Fair Value of Other Temporary Investments and Cash (Details) - USD ($) $ in Millions	Mar. 31, 2026	Dec. 31, 2025
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fair Value	$ 4,803	$ 4,916
Total Other Temporary Investments and Restricted Cash
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cost	219	264
Gross Unrealized Gains	27	29
Gross Unrealized Losses	(3)	(2)
Fair Value	243	291
Restricted Cash
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cost	33	71
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Fair Value	33	71
Other Cash Deposits
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cost	11	13
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Fair Value	11	13
Fixed Income Securities – Mutual Funds
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cost	164	167
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(3)	(2)
Fair Value	161	165
Equity Securities – Mutual Funds
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cost	11	13
Gross Unrealized Gains	27	29
Gross Unrealized Losses	0	0
Fair Value	$ 38	$ 42

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, before 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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