Financial Instruments - Summary of Cash and Available-for-Sale Securities by Significant Investment Category (Details) - USD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 10,182	$ 15,479
Level 2
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	13,114	18,684
Unrealized Gains	0	0
Unrealized Losses	(268)	(464)
Estimated Fair Value	12,846	18,220
Cash and cash equivalents \| Level 2
Debt Securities, Available-for-sale [Line Items]
Estimated Fair Value	2,932	3,205
Current Marketable Securities \| Level 2
Debt Securities, Available-for-sale [Line Items]
Estimated Fair Value	4,641	6,697
Non- Current Marketable Securities \| Level 2
Debt Securities, Available-for-sale [Line Items]
Estimated Fair Value	5,273	8,318
Cash and cash equivalents \| Level 1
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	2,932	3,205
Unrealized Gains	0	0
Unrealized Losses	0	0
Estimated Fair Value	2,932	3,205
Cash and cash equivalents \| Cash and cash equivalents \| Level 1
Debt Securities, Available-for-sale [Line Items]
Estimated Fair Value	2,932	3,205
Cash and cash equivalents \| Current Marketable Securities \| Level 1
Debt Securities, Available-for-sale [Line Items]
Estimated Fair Value	0	0
Cash and cash equivalents \| Non- Current Marketable Securities \| Level 1
Debt Securities, Available-for-sale [Line Items]
Estimated Fair Value	0	0
Certificates of deposit \| Level 2
Debt Securities, Available-for-sale [Line Items]
Amortized Cost		188
Unrealized Gains		0
Unrealized Losses		0
Estimated Fair Value		188
Certificates of deposit \| Cash and cash equivalents \| Level 2
Debt Securities, Available-for-sale [Line Items]
Estimated Fair Value		0
Certificates of deposit \| Current Marketable Securities \| Level 2
Debt Securities, Available-for-sale [Line Items]
Estimated Fair Value		188
Certificates of deposit \| Non- Current Marketable Securities \| Level 2
Debt Securities, Available-for-sale [Line Items]
Estimated Fair Value		0
U.S. treasury bills \| Level 2
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	529	767
Unrealized Gains	0	0
Unrealized Losses	0	0
Estimated Fair Value	529	767
U.S. treasury bills \| Cash and cash equivalents \| Level 2
Debt Securities, Available-for-sale [Line Items]
Estimated Fair Value	0	0
U.S. treasury bills \| Current Marketable Securities \| Level 2
Debt Securities, Available-for-sale [Line Items]
Estimated Fair Value	529	767
U.S. treasury bills \| Non- Current Marketable Securities \| Level 2
Debt Securities, Available-for-sale [Line Items]
Estimated Fair Value	0	0
U.S. treasury notes \| Level 2
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	4,643	7,781
Unrealized Gains	0	0
Unrealized Losses	(121)	(229)
Estimated Fair Value	4,522	7,552
U.S. treasury notes \| Cash and cash equivalents \| Level 2
Debt Securities, Available-for-sale [Line Items]
Estimated Fair Value	0	0
U.S. treasury notes \| Current Marketable Securities \| Level 2
Debt Securities, Available-for-sale [Line Items]
Estimated Fair Value	2,354	4,182
U.S. treasury notes \| Non- Current Marketable Securities \| Level 2
Debt Securities, Available-for-sale [Line Items]
Estimated Fair Value	2,168	3,370
Corporate debt securities \| Level 2
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	4,854	6,595
Unrealized Gains	0	0
Unrealized Losses	(141)	(226)
Estimated Fair Value	4,713	6,369
Corporate debt securities \| Cash and cash equivalents \| Level 2
Debt Securities, Available-for-sale [Line Items]
Estimated Fair Value	0	0
Corporate debt securities \| Current Marketable Securities \| Level 2
Debt Securities, Available-for-sale [Line Items]
Estimated Fair Value	1,680	1,560
Corporate debt securities \| Non- Current Marketable Securities \| Level 2
Debt Securities, Available-for-sale [Line Items]
Estimated Fair Value	3,033	4,809
Government debt securities \| Level 2
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	156	148
Unrealized Gains	0	0
Unrealized Losses	(6)	(9)
Estimated Fair Value	150	139
Government debt securities \| Cash and cash equivalents \| Level 2
Debt Securities, Available-for-sale [Line Items]
Estimated Fair Value	0	0
Government debt securities \| Current Marketable Securities \| Level 2
Debt Securities, Available-for-sale [Line Items]
Estimated Fair Value	78	0
Government debt securities \| Non- Current Marketable Securities \| Level 2
Debt Securities, Available-for-sale [Line Items]
Estimated Fair Value	$ 72	$ 139

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, before tax, of unrealized loss 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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