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Financial Instruments - Information on Debt and Equity Securities (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Debt Securities, Available-for-sale [Line Items]
Debt securities, amortized cost	$ 86	$ 89
Debt securities, gross unrealized gains	0	0
Debt securities, gross unrealized losses	0	0
Debt securities, fair value	86	89
Publicly traded equity securities, fair value	1,647	1,787
Total debt and publicly traded equity securities, fair value	1,733	1,876
Unrealized (loss) gains	(232)	163
U.S. government and agency securities
Debt Securities, Available-for-sale [Line Items]
Debt securities, amortized cost	80	84
Debt securities, gross unrealized gains	0	0
Debt securities, gross unrealized losses	0	0
Debt securities, fair value	80	84
Foreign government bonds
Debt Securities, Available-for-sale [Line Items]
Debt securities, amortized cost	2	5
Debt securities, gross unrealized gains	0	0
Debt securities, gross unrealized losses	0	0
Debt securities, fair value	2	5
Corporate notes and bonds
Debt Securities, Available-for-sale [Line Items]
Debt securities, amortized cost	4	0
Debt securities, gross unrealized gains	0	0
Debt securities, gross unrealized losses	0	0
Debt securities, fair value	$ 4	$ 0

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Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI), classified as current.

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