Financial Instruments - Summary of Cash and Available-for-Sale Securities by Significant Investment Category (Details) - USD ($) $ in Millions	Jun. 30, 2024	Dec. 31, 2023
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 8,429	$ 10,519
Level 2
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	10,907	13,426
Unrealized Gains	1	6
Unrealized Losses	(94)	(151)
Estimated Fair Value	10,814	13,281
Cash and cash equivalents \| Level 2
Debt Securities, Available-for-sale [Line Items]
Estimated Fair Value	2,478	2,907
Current Marketable Securities \| Level 2
Debt Securities, Available-for-sale [Line Items]
Estimated Fair Value	6,010	5,697
Non- Current Marketable Securities \| Level 2
Debt Securities, Available-for-sale [Line Items]
Estimated Fair Value	2,326	4,677
Cash and cash equivalents \| Level 1
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	2,478	2,907
Unrealized Gains	0	0
Unrealized Losses	0	0
Estimated Fair Value	2,478	2,907
Cash and cash equivalents \| Cash and cash equivalents \| Level 1
Debt Securities, Available-for-sale [Line Items]
Estimated Fair Value	2,478	2,907
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	29	27
Unrealized Gains	0	0
Unrealized Losses	0	0
Estimated Fair Value	29	27
Certificates of deposit \| Cash and cash equivalents \| Level 2
Debt Securities, Available-for-sale [Line Items]
Estimated Fair Value	0	0
Certificates of deposit \| Current Marketable Securities \| Level 2
Debt Securities, Available-for-sale [Line Items]
Estimated Fair Value	29	27
Certificates of deposit \| Non- Current Marketable Securities \| Level 2
Debt Securities, Available-for-sale [Line Items]
Estimated Fair Value	0	0
U.S. treasury bills \| Level 2
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	588	807
Unrealized Gains	0	0
Unrealized Losses	0	0
Estimated Fair Value	588	807
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	588	807
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	3,593	4,407
Unrealized Gains	0	3
Unrealized Losses	(45)	(67)
Estimated Fair Value	3,548	4,343
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	2,642	2,664
U.S. treasury notes \| Non- Current Marketable Securities \| Level 2
Debt Securities, Available-for-sale [Line Items]
Estimated Fair Value	906	1,679
Corporate debt securities \| Level 2
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	4,023	5,067
Unrealized Gains	1	3
Unrealized Losses	(47)	(81)
Estimated Fair Value	3,977	4,989
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	2,594	2,082
Corporate debt securities \| Non- Current Marketable Securities \| Level 2
Debt Securities, Available-for-sale [Line Items]
Estimated Fair Value	1,383	2,907
Government debt securities \| Level 2
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	196	211
Unrealized Gains	0	0
Unrealized Losses	(2)	(3)
Estimated Fair Value	194	208
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	157	117
Government debt securities \| Non- Current Marketable Securities \| Level 2
Debt Securities, Available-for-sale [Line Items]
Estimated Fair Value	$ 37	$ 91

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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