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Financial Instruments - Information on Available-for-sale Investments (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
Debt Securities, Available-for-sale [Line Items]
Debt securities, amortized cost	$ 454		$ 86
Debt securities, unrealized gains	0		0
Debt securities, unrealized losses	0		0
Debt securities, fair value	454		86
Publicly traded equity securities, fair value	1,397		1,647
Total debt and publicly traded equity securities, fair value	1,851		1,733
Unrealized net losses	225	$ 181
Commercial paper
Debt Securities, Available-for-sale [Line Items]
Debt securities, amortized cost	372		0
Debt securities, unrealized gains	0		0
Debt securities, unrealized losses	0		0
Debt securities, fair value	372		0
U.S. government and agency securities
Debt Securities, Available-for-sale [Line Items]
Debt securities, amortized cost	75		80
Debt securities, unrealized gains	0		0
Debt securities, unrealized losses	0		0
Debt securities, fair value	75		80
Corporate notes and bonds
Debt Securities, Available-for-sale [Line Items]
Debt securities, amortized cost	4		4
Debt securities, unrealized gains	0		0
Debt securities, unrealized losses	0		0
Debt securities, fair value	4		4
Foreign government bonds
Debt Securities, Available-for-sale [Line Items]
Debt securities, amortized cost	3		2
Debt securities, unrealized gains	0		0
Debt securities, unrealized losses	0		0
Debt securities, fair value	$ 3		$ 2

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