Valuation of debt and equity investments and certain liabilities - Investments at Fair Value (Details) - USD ($) $ in Millions	Jun. 30, 2026	Dec. 31, 2025
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and Cash Equivalents	$ 3,660	$ 3,225
Short-term investments	3,341	1,656
Other Long-Term Assets	15	16
Measured at fair value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and Cash Equivalents	3,272	2,841
Short-term investments	3,341	1,656
Other Long-Term Assets	11	11
Money market funds \| Measured at fair value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and Cash Equivalents	823	844
Short-term investments	0	0
Other Long-Term Assets	0	0
Corporate obligations \| Measured at fair value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and Cash Equivalents	541	517
Short-term investments	1,013	522
Other Long-Term Assets	0	0
U.S. government and agency securities \| Measured at fair value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and Cash Equivalents	1,659	1,296
Short-term investments	2,032	1,035
Other Long-Term Assets	0	0
Non-U.S. government and agency securities \| Measured at fair value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and Cash Equivalents	249	184
Short-term investments	296	99
Other Long-Term Assets	0	0
Mutual funds \| Measured at fair value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and Cash Equivalents	0	0
Short-term investments	0	0
Other Long-Term Assets	11	11
Other investments \| Other measurement basis
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and Cash Equivalents	0	0
Short-term investments	0	0
Other Long-Term Assets	4	5
Cash on hand \| Other measurement basis
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and Cash Equivalents	388	384
Short-term investments	0	0
Other Long-Term Assets	$ 0	$ 0

Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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