Accounting Policies and Supplemental Disclosures - Other Income (Expense), Net (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Accounting Policies [Abstract]
Marketable equity securities valuation gains (losses)	$ (129)	$ 200	$ (48)	$ 404
Equity warrant valuation gains (losses)	(50)	300	1,194	566
Upward adjustments relating to equity investments in private companies	155	320	1,661	320
Foreign currency gains (losses)	(107)	112	(28)	(97)
Other, net	(32)	(7)	16	(28)
Total other income (expense), net	$ (163)	$ 925	$ 2,795	$ 1,165