FAIR VALUE MEASUREMENTS - Fair Value of Other Temporary Investments and Cash (Details) - USD ($) $ in Millions	Dec. 31, 2025	Dec. 31, 2024
Other Temporary Investments And Restricted Cash
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cost	$ 264	$ 236
Gross unrealized gains	29	27
Gross unrealized losses	(2)	(5)
Fair value	291	258
Restricted Cash
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cost	71	43
Gross unrealized gains	0	0
Gross unrealized losses	0	0
Fair value	71	43
Other Cash Deposits
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cost	13	13
Gross unrealized gains	0	0
Gross unrealized losses	0	0
Fair value	13	13
Fixed Income Securities – Mutual Funds
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cost	167	167
Gross unrealized gains	0	0
Gross unrealized losses	(2)	(5)
Fair value	165	162
Equity Securities – Mutual Funds
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cost	13	13
Gross unrealized gains	29	27
Gross unrealized losses	0	0
Fair value	$ 42	$ 40

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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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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