Accounting Policies and Supplemental Disclosures - Other Income (Expense), Net (Details) - USD ($) shares in Millions, $ in Millions	3 Months Ended		6 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Jun. 30, 2024	Jun. 30, 2023	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023	Dec. 31, 2023
Schedule of Investments [Line Items]
Marketable equity securities valuation gains (losses)	$ (117)	$ 1,196			$ (1,800)	$ 1,015
Equity warrant valuation gains (losses)	80	(27)			(421)	(188)
Upward adjustments relating to equity investments in private companies	2	7			13	33
Foreign currency gains (losses)	17	(94)			(195)	(15)
Other, net	(9)	(51)			(315)	(196)
Total other income (expense), net	(27)	1,031			(2,718)	649
Loss from operations	17,411	11,188			47,390	23,643
Net loss	15,328	9,879			39,244	19,801	$ 49,868	$ 20,079
Equity method investment, nonconsolidated investee
Schedule of Investments [Line Items]
Marketable equity securities valuation gains (losses)	$ (348)	$ 1,200			$ (1,900)	$ 926
Equity investment, shares held (in shares)	158				158		158
Equity investment, ownership percentage	16.00%				16.00%		16.00%
Equity investment, voting interest	15.00%				15.00%		15.00%
Equity investment, fair value	$ 1,800				$ 1,800		$ 1,800		$ 3,700
Revenues			$ 2,362	$ 1,782
Gross profit (loss)			(978)	(947)
Loss from operations			(2,859)	(2,718)
Net loss			$ (2,903)	$ (2,544)