Short-term and Long-term Investments, Restricted Deposits - Schedule of Short-term and Long-term Investments and Restricted Deposits by Investment Type (Details) - USD ($) $ in Millions	Mar. 31, 2025	Dec. 31, 2024
Debt Securities
Gross Unrealized Gains	$ 130	$ 73
Gross Unrealized Losses	(566)	(727)
Equity securities	13	14
Private equity investments	878	851
Life insurance contracts	191	196
Total, Amortized Cost	22,585	22,095
Total, Fair Value	22,149	21,441
U.S. Treasury securities and obligations of U.S. government corporations and agencies
Debt Securities
Amortized Cost	571	593
Gross Unrealized Gains	3	2
Gross Unrealized Losses	(2)	(4)
Fair Value	572	591
Corporate securities
Debt Securities
Amortized Cost	11,350	10,820
Gross Unrealized Gains	82	47
Gross Unrealized Losses	(275)	(360)
Fair Value	11,157	10,507
Restricted certificates of deposit
Debt Securities
Amortized Cost	4	4
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Fair Value	4	4
Restricted cash equivalents
Debt Securities
Amortized Cost	72	93
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Fair Value	72	93
Short-term time deposits
Debt Securities
Amortized Cost	193	425
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Fair Value	193	425
Municipal securities
Debt Securities
Amortized Cost	4,187	4,174
Gross Unrealized Gains	14	7
Gross Unrealized Losses	(125)	(151)
Fair Value	4,076	4,030
Asset-backed securities
Debt Securities
Amortized Cost	1,955	1,820
Gross Unrealized Gains	18	13
Gross Unrealized Losses	(15)	(21)
Fair Value	1,958	1,812
Residential mortgage-backed securities
Debt Securities
Amortized Cost	1,841	1,807
Gross Unrealized Gains	7	1
Gross Unrealized Losses	(99)	(129)
Fair Value	1,749	1,679
Commercial mortgage-backed securities
Debt Securities
Amortized Cost	1,330	1,298
Gross Unrealized Gains	6	3
Gross Unrealized Losses	(50)	(62)
Fair Value	$ 1,286	$ 1,239

Investments, Debt Securities, Equity Method Investments And Other, Amortized Cost

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Investments, Debt Securities, Equity Securities And Other, Fair Value

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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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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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This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

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Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI), classified as current.

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This item represents the amount that could be realized under a life insurance contract or contracts owned by the Entity as of the date of the statement of financial position. Such Entity-owned life insurance policies are commonly known as corporate-owned life insurance (COLI) or bank-owned life insurance (BOLI).

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