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Financial Instruments - Information on Available-for-sale Investments (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2025	Mar. 31, 2024	Dec. 31, 2024
Debt Securities, Available-for-sale [Line Items]
Debt securities, amortized cost	$ 690		$ 536
Debt securities, unrealized gains	0		0
Debt securities, unrealized losses	0		0
Debt securities, fair value	690		536
Publicly traded equity securities, fair value	1,033		920
Total debt and publicly traded equity securities, fair value	1,723		1,456
Unrealized net gains	115	$ 143
Commercial paper
Debt Securities, Available-for-sale [Line Items]
Debt securities, amortized cost	599		348
Debt securities, unrealized gains	0		0
Debt securities, unrealized losses	0		0
Debt securities, fair value	599		348
U.S. government and agency securities
Debt Securities, Available-for-sale [Line Items]
Debt securities, amortized cost	91		188
Debt securities, unrealized gains	0		0
Debt securities, unrealized losses	0		0
Debt securities, fair value	$ 91		$ 188

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