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v3.25.4

Commitments and contingencies - Narrative (Details) | 12 Months Ended |  |  |
--- | --- | --- | --- | ---
Dec. 31, 2025 USD ($) | Dec. 31, 2024 USD ($) | Dec. 31, 2023 USD ($) | Nov. 30, 2024 party | Jan. 31, 2017 USD ($) | Dec. 31, 2000 party
Other Commitments [Line Items] |  |  |  |  |  |
Potential liabilities related to litigation and environmental matters | $ 3,300,000 | $ 6,600,000 |  |  |  |
Insurance receivables | $ 0 | 459,000 |  |  |  |
Number of parties issued general notice letters | party |  |  |  |  |  | 150
Number of other responsible parties | party |  |  |  | 60 |  | 100
Environmental remediation period (in years) |  |  |  |  | 13 years |
Environmental remediation, percent of site to be remediated |  |  |  |  | 100.00% |
Maximum commitment terms (in years) | 45 years |  |  |  |  |
Purchased under various commitments during the year | $ 135,300,000 | $ 128,300,000 | $ 128,700,000 |  |  |
Guarantor obligations, maximum exposure, undiscounted | 11,500,000 |  |  |  |  |
Amount outstanding under guarantees that is reflected on balance sheet | 0 |  |  |  |  |
Letters of credit set to expire - 2026 | 11,900,000 |  |  |  |  |
Letters of credit set to expire - 2027 | 11,300,000 |  |  |  |  |
Letters of credit set to expire - 2028 | 175,000 |  |  |  |  |
Outstanding letters of credit | $ 0 |  |  |  |  |
Surety bond expiration period | 12 months |  |  |  |  |
Amount of surety bonds outstanding | $ 858,300,000 |  |  |  |  |
Letter of Credit |  |  |  |  |  |
Other Commitments [Line Items] |  |  |  |  |  |
Line of credit, maximum borrowing capacity | $ 23,400,000 |  |  |  |  |
Minimum |  |  |  |  |  |
Other Commitments [Line Items] |  |  |  |  |  |
Environmental remediation expected costs |  |  |  |  | $ 1,000,000,000 |
Maximum |  |  |  |  |  |
Other Commitments [Line Items] |  |  |  |  |  |
Environmental remediation expected costs |  |  |  |  | $ 2,000,000,000 |

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