Financial Instruments - Schedule of Cash and Available-for-Sale Securities by Significant Investment Category (Details) - USD ($) $ in Millions	Mar. 31, 2026	Dec. 31, 2025
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 5,556	$ 5,533
Level 2
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	7,464	8,128
Unrealized Gains	3	11
Unrealized Losses	(11)	(4)
Estimated Fair Value	7,456	8,135
Cash and Cash Equivalents \| Level 2
Debt Securities, Available-for-sale [Line Items]
Estimated Fair Value	1,908	2,595
Current Marketable Securities \| Level 2
Debt Securities, Available-for-sale [Line Items]
Estimated Fair Value	3,297	3,204
Non- Current Marketable Securities \| Level 2
Debt Securities, Available-for-sale [Line Items]
Estimated Fair Value	2,251	2,336
Cash and Cash Equivalents \| Level 1
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	1,908	2,595
Unrealized Gains	0	0
Unrealized Losses	0	0
Estimated Fair Value	1,908	2,595
Cash and Cash Equivalents \| Cash and Cash Equivalents \| Level 1
Debt Securities, Available-for-sale [Line Items]
Estimated Fair Value	1,908	2,595
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	61	91
Unrealized Gains	0	0
Unrealized Losses	0	0
Estimated Fair Value	61	91
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	61	86
Certificates of deposit \| Non- Current Marketable Securities \| Level 2
Debt Securities, Available-for-sale [Line Items]
Estimated Fair Value	0	5
U.S. treasury bills \| Level 2
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	610	653
Unrealized Gains	0	0
Unrealized Losses	0	0
Estimated Fair Value	610	653
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	610	653
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	2,230	2,188
Unrealized Gains	1	5
Unrealized Losses	(5)	(3)
Estimated Fair Value	2,226	2,190
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	1,233	1,185
U.S. treasury notes \| Non- Current Marketable Securities \| Level 2
Debt Securities, Available-for-sale [Line Items]
Estimated Fair Value	993	1,005
Corporate debt securities \| Level 2
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	2,599	2,535
Unrealized Gains	2	6
Unrealized Losses	(6)	(1)
Estimated Fair Value	2,595	2,540
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	1,391	1,250
Corporate debt securities \| Non- Current Marketable Securities \| Level 2
Debt Securities, Available-for-sale [Line Items]
Estimated Fair Value	1,204	1,290
Government debt securities \| Level 2
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	56	66
Unrealized Gains	0	0
Unrealized Losses	0	0
Estimated Fair Value	56	66
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	2	30
Government debt securities \| Non- Current Marketable Securities \| Level 2
Debt Securities, Available-for-sale [Line Items]
Estimated Fair Value	$ 54	$ 36

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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