Financial Instruments - Fair Values on Recurring Basis (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Equity Securities, FV-NI, Gain (Loss)
Equity securities, unrealized gain (loss)	$ (1,300)	$ 1,000	$ (13,600)
Recurring
Schedule of Investments [Line Items]
Cash	17,055	11,706
Cost or Amortized Cost
Cash, cash equivalents and short-term investments	101,532	82,971
Gross Unrealized Gains
Cash equivalents and marketable securities	6	1
Gross Unrealized Losses
Cash equivalents and marketable securities	(121)	(347)
Total Estimated Fair Value
Cash, cash equivalents and short-term investments	104,735	87,283
Less: Restricted cash, cash equivalents, and marketable securities	(3,533)	(503)
Total cash, cash equivalents, and marketable securities	101,202	86,780
Recurring | Level 1 securities
Total Estimated Fair Value
Equity securities	3,318	4,658
Recurring | Level 1 securities | Money market funds
Schedule of Investments [Line Items]
Money market funds	28,282	39,160
Recurring | Level 1 securities | Money market funds | Money market funds
Schedule of Investments [Line Items]
Money market funds	28,282
Recurring | Level 2 securities | Foreign government and agency securities
Cost or Amortized Cost
Cash equivalents and marketable securities	177	505
Gross Unrealized Gains
Cash equivalents and marketable securities	0	0
Gross Unrealized Losses
Cash equivalents and marketable securities	0	0
Total Estimated Fair Value
Cash equivalents and marketable securities	177	505
Recurring | Level 2 securities | U.S. government and agency securities
Cost or Amortized Cost
Cash equivalents and marketable securities	3,452	1,789
Gross Unrealized Gains
Cash equivalents and marketable securities	1	1
Gross Unrealized Losses
Cash equivalents and marketable securities	(52)	(91)
Total Estimated Fair Value
Cash equivalents and marketable securities	3,401	1,699
Recurring | Level 2 securities | Corporate debt securities
Cost or Amortized Cost
Cash equivalents and marketable securities	50,959	27,996
Gross Unrealized Gains
Cash equivalents and marketable securities	3	0
Gross Unrealized Losses
Cash equivalents and marketable securities	(50)	(191)
Total Estimated Fair Value
Cash equivalents and marketable securities	50,912	27,805
Recurring | Level 2 securities | Asset-backed securities
Cost or Amortized Cost
Cash equivalents and marketable securities	1,539	1,707
Gross Unrealized Gains
Cash equivalents and marketable securities	2	0
Gross Unrealized Losses
Cash equivalents and marketable securities	(18)	(61)
Total Estimated Fair Value
Cash equivalents and marketable securities	1,523	1,646
Recurring | Level 2 securities | Other debt securities
Cost or Amortized Cost
Cash equivalents and marketable securities	68	108
Gross Unrealized Gains
Cash equivalents and marketable securities	0	0
Gross Unrealized Losses
Cash equivalents and marketable securities	(1)	(4)
Total Estimated Fair Value
Cash equivalents and marketable securities	$ 67	$ 104