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	Sep. 30, 2026	Dec. 31, 2025
Debt securities:
Gross Unrealized Gains	$ 11	$ 256
Gross Unrealized Losses	(694)	(325)
Equity securities	1	1
Private equity investments	1,001	915
Life insurance contracts	229	217
Total, Amortized Cost	19,833	20,948
Total, Fair Value	19,150	20,879
U.S. Treasury securities and obligations of U.S. government corporations and agencies
Debt securities:
Amortized Cost	568	533
Gross Unrealized Gains	0	3
Gross Unrealized Losses	(9)	(1)
Fair Value	559	535
Corporate securities
Debt securities:
Amortized Cost	10,518	10,642
Gross Unrealized Gains	8	166
Gross Unrealized Losses	(346)	(146)
Fair Value	10,180	10,662
Restricted certificates of deposit
Debt securities:
Amortized Cost	1	1
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Fair Value	1	1
Restricted cash equivalents
Debt securities:
Amortized Cost	187	69
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Fair Value	187	69
Short-term time deposits
Debt securities:
Amortized Cost	72	205
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Fair Value	72	205
Municipal securities
Debt securities:
Amortized Cost	3,191	3,790
Gross Unrealized Gains	0	37
Gross Unrealized Losses	(132)	(69)
Fair Value	3,059	3,758
Asset-backed securities
Debt securities:
Amortized Cost	1,387	1,656
Gross Unrealized Gains	2	20
Gross Unrealized Losses	(24)	(10)
Fair Value	1,365	1,666
Residential mortgage-backed securities
Debt securities:
Amortized Cost	1,641	1,763
Gross Unrealized Gains	0	21
Gross Unrealized Losses	(142)	(70)
Fair Value	1,499	1,714
Commercial mortgage-backed securities
Debt securities:
Amortized Cost	1,037	1,156
Gross Unrealized Gains	1	9
Gross Unrealized Losses	(41)	(29)
Fair Value	$ 997	$ 1,136

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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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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