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Financial Instruments - Information on Available-for-sale Investments (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
Debt Securities, Available-for-sale [Line Items]
Debt securities, amortized cost	$ 81		$ 81		$ 337
Debt securities, unrealized gains	0		0		0
Debt securities, unrealized losses	0		0		0
Debt securities, fair value	81		81		337
Publicly traded equity securities, fair value	984		984		764
Total debt and publicly traded equity securities, fair value	1,065		1,065		1,101
Unrealized net losses (gains)	42	$ 61	(82)	$ 327
U.S. government and agency securities
Debt Securities, Available-for-sale [Line Items]
Debt securities, amortized cost	81		81		72
Debt securities, unrealized gains	0		0		0
Debt securities, unrealized losses	0		0		0
Debt securities, fair value	81		81		72
Commercial paper
Debt Securities, Available-for-sale [Line Items]
Debt securities, amortized cost	0		0		252
Debt securities, unrealized gains	0		0		0
Debt securities, unrealized losses	0		0		0
Debt securities, fair value	0		0		252
Corporate notes and bonds
Debt Securities, Available-for-sale [Line Items]
Debt securities, amortized cost	0		0		13
Debt securities, unrealized gains	0		0		0
Debt securities, unrealized losses	0		0		0
Debt securities, fair value	$ 0		$ 0		$ 13

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