Short-term and Long-term Investments, Restricted Deposits - By Investment Type (Details) - USD ($) $ in Millions	Dec. 31, 2022	Dec. 31, 2021
Debt Securities
Gross Unrealized Gains	$ 20	$ 243
Gross Unrealized Losses	(1,364)	(114)
Equity securities	5	326
Private equity investments	529	587
Life insurance contracts	169	186
Total, Amortized Cost	19,566	16,521
Total, Fair Value	18,222	16,650
U.S. Treasury securities and obligations of U.S. government corporations and agencies
Debt Securities
Amortized Cost	695	642
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(16)	(2)
Fair Value	679	640
Corporate securities
Debt Securities
Amortized Cost	10,127	8,145
Gross Unrealized Gains	12	130
Gross Unrealized Losses	(778)	(75)
Fair Value	9,361	8,200
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	256	96
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Fair Value	256	96
Short-term time deposits
Debt Securities
Amortized Cost	204	109
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Fair Value	204	109
Municipal securities
Debt Securities
Amortized Cost	4,055	3,398
Gross Unrealized Gains	6	85
Gross Unrealized Losses	(280)	(15)
Fair Value	3,781	3,468
Asset-backed securities
Debt Securities
Amortized Cost	1,396	1,308
Gross Unrealized Gains	0	5
Gross Unrealized Losses	(70)	(5)
Fair Value	1,326	1,308
Residential mortgage-backed securities
Debt Securities
Amortized Cost	1,165	850
Gross Unrealized Gains	2	10
Gross Unrealized Losses	(121)	(7)
Fair Value	1,046	853
Commercial mortgage-backed securities
Debt Securities
Amortized Cost	961	870
Gross Unrealized Gains	0	13
Gross Unrealized Losses	(99)	(10)
Fair Value	$ 862	$ 873

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 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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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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