Financial Instruments - Fair Values on Recurring Basis (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024	Dec. 31, 2024
Equity Securities, FV-NI, Gain (Loss)
Equity securities, unrealized gain (loss)	$ 393	$ 443	$ 188	$ (1,700)
Recurring
Schedule of Investments [Line Items]
Cash	16,083		16,083		$ 17,055
Debt Securities, Available-for-sale
Gross unrealized gains	37		37
Gross unrealized losses	(63)		(63)
Cash, Cash Equivalents, and Marketable Securities
Cash, cash equivalents and marketable securities	96,892		96,892		104,735
Cash, cash equivalents and marketable securities, amortized cost	93,769		93,769
Less: Restricted cash, cash equivalents, and marketable securities	(3,712)		(3,712)		(3,533)
Total cash, cash equivalents, and marketable securities	93,180		93,180		101,202
Recurring | Level 1 securities
Schedule of Investments [Line Items]
Equity securities	3,149		3,149		3,318
Recurring | Level 1 securities | Money market funds
Schedule of Investments [Line Items]
Money market funds	18,058		18,058		28,282
Recurring | Level 1 securities | Money market funds | Money market funds
Schedule of Investments [Line Items]
Money market funds	18,058		18,058
Recurring | Level 2 securities | Foreign government and agency securities
Debt Securities, Available-for-sale
Fixed income securities, amortized cost	84		84
Gross unrealized gains	0		0
Gross unrealized losses	0		0
Fixed income securities	84		84		177
Recurring | Level 2 securities | U.S. government and agency securities
Debt Securities, Available-for-sale
Fixed income securities, amortized cost	5,057		5,057
Gross unrealized gains	5		5
Gross unrealized losses	(32)		(32)
Fixed income securities	5,030		5,030		3,401
Recurring | Level 2 securities | Corporate debt securities
Debt Securities, Available-for-sale
Fixed income securities, amortized cost	52,634		52,634
Gross unrealized gains	26		26
Gross unrealized losses	(19)		(19)
Fixed income securities	52,641		52,641		50,912
Recurring | Level 2 securities | Asset-backed securities
Debt Securities, Available-for-sale
Fixed income securities, amortized cost	1,813		1,813
Gross unrealized gains	6		6
Gross unrealized losses	(12)		(12)
Fixed income securities	1,807		1,807		1,523
Recurring | Level 2 securities | Other debt securities
Debt Securities, Available-for-sale
Fixed income securities, amortized cost	40		40
Gross unrealized gains	0		0
Gross unrealized losses	0		0
Fixed income securities	$ 40		$ 40		$ 67