Assets and liabilities at fair value - Schedule of Assets and Liabilities Recorded at Fair Value (Details) - Level 2 - USD ($) $ in Millions |
Jun. 30, 2026 |
Dec. 31, 2025 |
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| Unsecured senior notes | ||
| Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ||
| Carrying Amount | $ 3,830 | $ 3,828 |
| Fair Value | 3,773 | 3,833 |
| Private placement notes | ||
| Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ||
| Carrying Amount | 300 | 300 |
| Fair Value | $ 299 | $ 300 |
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount, after deduction of unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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