Fair Value Measurements - Financial Instruments Not Required to be Measured at Fair Value (Details) - USD ($) $ in Millions	Sep. 30, 2025	Dec. 31, 2024
Carrying Value \| Level 2
Estimated fair values of the company's financial instruments that are not measured at fair value on a recurring basis
Marketable securities, current	$ 53	$ 130
Carrying Value \| Level 2 \| 2028 Notes (4.250% Senior Notes)
Estimated fair values of the company's financial instruments that are not measured at fair value on a recurring basis
Debt	505	541
Carrying Value \| Level 2 \| 2029 Notes (1.125% Convertible Senior Notes)
Estimated fair values of the company's financial instruments that are not measured at fair value on a recurring basis
Debt	565	563
Carrying Value \| Level 3
Estimated fair values of the company's financial instruments that are not measured at fair value on a recurring basis
Notes receivable, including noncurrent portion	10	9
Fair Value \| Level 2
Estimated fair values of the company's financial instruments that are not measured at fair value on a recurring basis
Marketable securities, current	53	130
Fair Value \| Level 2 \| 2028 Notes (4.250% Senior Notes)
Estimated fair values of the company's financial instruments that are not measured at fair value on a recurring basis
Debt	502	517
Fair Value \| Level 2 \| 2029 Notes (1.125% Convertible Senior Notes)
Estimated fair values of the company's financial instruments that are not measured at fair value on a recurring basis
Debt	683	725
Fair Value \| Level 3
Estimated fair values of the company's financial instruments that are not measured at fair value on a recurring basis
Notes receivable, including noncurrent portion	10	9
Cash \| Carrying Value \| Level 1
Estimated fair values of the company's financial instruments that are not measured at fair value on a recurring basis
Cash and cash equivalents	1,833	1,613
Cash \| Fair Value \| Level 1
Estimated fair values of the company's financial instruments that are not measured at fair value on a recurring basis
Cash and cash equivalents	1,833	1,613
Cash Equivalents \| Carrying Value \| Level 2
Estimated fair values of the company's financial instruments that are not measured at fair value on a recurring basis
Cash and cash equivalents	943	1,216
Cash Equivalents \| Fair Value \| Level 2
Estimated fair values of the company's financial instruments that are not measured at fair value on a recurring basis
Cash and cash equivalents	$ 943	$ 1,216

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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Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

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Fair value of investment in debt security measured at amortized cost (held-to-maturity).

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Fair value portion of an agreement for an unconditional promise by the maker to pay the holder a definite sum of money at a future date.

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