Financial Instruments - Fair Values on Recurring Basis (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023	Dec. 31, 2023
Equity Securities, FV-NI, Gain (Loss)
Equity securities, unrealized gain (loss)	$ (145)	$ 1,200	$ (1,800)	$ 1,000
Recurring
Schedule of Investments [Line Items]
Cash	15,401		15,401		$ 11,706
Debt Securities, Available-for-sale
Gross unrealized gains	9		9
Gross unrealized losses	(124)		(124)
Cash, Cash Equivalents, and Marketable Securities
Cash, cash equivalents and marketable securities	91,637		91,637		87,283
Cash, cash equivalents and marketable securities, amortized cost	88,888		88,888
Less: Restricted cash, cash equivalents, and marketable securities	(3,586)		(3,586)		(503)
Total cash, cash equivalents, and marketable securities	88,051		88,051		86,780
Recurring | Level 1 securities
Schedule of Investments [Line Items]
Equity securities	2,864		2,864		4,658
Recurring | Level 1 securities | Money market funds
Schedule of Investments [Line Items]
Money market funds	28,793		28,793		39,160
Recurring | Level 1 securities | Money market funds | Money market funds
Schedule of Investments [Line Items]
Money market funds	28,793		28,793
Recurring | Level 2 securities | Foreign government and agency securities
Debt Securities, Available-for-sale
Fixed income securities, amortized cost	302		302
Gross unrealized gains	0		0
Gross unrealized losses	0		0
Fixed income securities	302		302		505
Recurring | Level 2 securities | U.S. government and agency securities
Debt Securities, Available-for-sale
Fixed income securities, amortized cost	2,309		2,309
Gross unrealized gains	1		1
Gross unrealized losses	(51)		(51)
Fixed income securities	2,259		2,259		1,699
Recurring | Level 2 securities | Corporate debt securities
Debt Securities, Available-for-sale
Fixed income securities, amortized cost	41,001		41,001
Gross unrealized gains	7		7
Gross unrealized losses	(52)		(52)
Fixed income securities	40,956		40,956		27,805
Recurring | Level 2 securities | Asset-backed securities
Debt Securities, Available-for-sale
Fixed income securities, amortized cost	1,018		1,018
Gross unrealized gains	1		1
Gross unrealized losses	(20)		(20)
Fixed income securities	999		999		1,646
Recurring | Level 2 securities | Other debt securities
Debt Securities, Available-for-sale
Fixed income securities, amortized cost	64		64
Gross unrealized gains	0		0
Gross unrealized losses	(1)		(1)
Fixed income securities	$ 63		$ 63		$ 104