Financial Instruments and Fair Value Measurements - Summary of Cash and Available-for-Sale Securities by Significant Investment Category (Details) - USD ($) $ in Millions	Dec. 31, 2025	Dec. 31, 2024
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 5,533	$ 7,614
Level 2
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	8,128	9,541
Unrealized Gains	11	6
Unrealized Losses	(4)	(28)
Fair Value	8,135	9,519
Cash and Cash Equivalents \| Level 2
Debt Securities, Available-for-sale [Line Items]
Fair Value	2,595	1,927
Current Marketable Securities \| Level 2
Debt Securities, Available-for-sale [Line Items]
Fair Value	3,204	5,098
Non- Current Marketable Securities \| Level 2
Debt Securities, Available-for-sale [Line Items]
Fair Value	2,336	2,494
Cash and Cash Equivalents \| Level 1
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	2,595	1,927
Unrealized Gains	0	0
Unrealized Losses	0	0
Fair Value	2,595	1,927
Cash and Cash Equivalents \| Cash and Cash Equivalents \| Level 1
Debt Securities, Available-for-sale [Line Items]
Fair Value	2,595	1,927
Cash and Cash Equivalents \| Current Marketable Securities \| Level 1
Debt Securities, Available-for-sale [Line Items]
Fair Value	0	0
Cash and Cash Equivalents \| Non- Current Marketable Securities \| Level 1
Debt Securities, Available-for-sale [Line Items]
Fair Value	0	0
Certificates of deposit \| Level 2
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	91	52
Unrealized Gains	0	0
Unrealized Losses	0	0
Fair Value	91	52
Certificates of deposit \| Cash and Cash Equivalents \| Level 2
Debt Securities, Available-for-sale [Line Items]
Fair Value	0	0
Certificates of deposit \| Current Marketable Securities \| Level 2
Debt Securities, Available-for-sale [Line Items]
Fair Value	86	52
Certificates of deposit \| Non- Current Marketable Securities \| Level 2
Debt Securities, Available-for-sale [Line Items]
Fair Value	5	0
U.S. treasury bills \| Level 2
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	653	786
Unrealized Gains	0	0
Unrealized Losses	0	0
Fair Value	653	786
U.S. treasury bills \| Cash and Cash Equivalents \| Level 2
Debt Securities, Available-for-sale [Line Items]
Fair Value	0	0
U.S. treasury bills \| Current Marketable Securities \| Level 2
Debt Securities, Available-for-sale [Line Items]
Fair Value	653	786
U.S. treasury bills \| Non- Current Marketable Securities \| Level 2
Debt Securities, Available-for-sale [Line Items]
Fair Value	0	0
U.S. treasury notes \| Level 2
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	2,188	3,048
Unrealized Gains	5	3
Unrealized Losses	(3)	(15)
Fair Value	2,190	3,036
U.S. treasury notes \| Cash and Cash Equivalents \| Level 2
Debt Securities, Available-for-sale [Line Items]
Fair Value	0	0
U.S. treasury notes \| Current Marketable Securities \| Level 2
Debt Securities, Available-for-sale [Line Items]
Fair Value	1,185	1,958
U.S. treasury notes \| Non- Current Marketable Securities \| Level 2
Debt Securities, Available-for-sale [Line Items]
Fair Value	1,005	1,078
Corporate debt securities \| Level 2
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	2,535	3,590
Unrealized Gains	6	3
Unrealized Losses	(1)	(13)
Fair Value	2,540	3,580
Corporate debt securities \| Cash and Cash Equivalents \| Level 2
Debt Securities, Available-for-sale [Line Items]
Fair Value	0	0
Corporate debt securities \| Current Marketable Securities \| Level 2
Debt Securities, Available-for-sale [Line Items]
Fair Value	1,250	2,172
Corporate debt securities \| Non- Current Marketable Securities \| Level 2
Debt Securities, Available-for-sale [Line Items]
Fair Value	1,290	1,408
Government debt securities \| Level 2
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	66	138
Unrealized Gains	0	0
Unrealized Losses	0	0
Fair Value	66	138
Government debt securities \| Cash and Cash Equivalents \| Level 2
Debt Securities, Available-for-sale [Line Items]
Fair Value	0	0
Government debt securities \| Current Marketable Securities \| Level 2
Debt Securities, Available-for-sale [Line Items]
Fair Value	30	130
Government debt securities \| Non- Current Marketable Securities \| Level 2
Debt Securities, Available-for-sale [Line Items]
Fair Value	$ 36	$ 8

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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