Commitments and contingencies (Details) - USD ($) |
Mar. 31, 2026 |
Dec. 31, 2025 |
Mar. 31, 2025 |
|---|---|---|---|
| Loss Contingencies [Line Items] | |||
| Potential liabilities related to litigation and environmental matters | $ 3,200,000 | $ 3,300,000 | $ 3,400,000 |
| Loss contingency receivable | 145,000 | $ 0 | $ 0 |
| 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 current year | 756,000 | ||
| Letters of credit set to expire in next fiscal year | 50,900,000 | ||
| Letters of credit set to expire, year two | 175,000 | ||
| Outstanding letters of credit | $ 0 | ||
| Surety bond expiration period | 12 months | ||
| Amount of surety bonds outstanding | $ 990,400,000 | ||
| Letter of Credit | |||
| Loss Contingencies [Line Items] | |||
| Line of credit facility, maximum borrowing capacity | $ 51,800,000 |
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- Definition Amount of surety bonds outstanding related to construction contracts and reclamation obligations. No definition available.
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- Definition Letters of Credit Set to Expire, Year Two No definition available.
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- Definition Letters of credit set to expire current year. No definition available.
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- Definition Letters of credit set to expire in next fiscal year. No definition available.
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- Definition Surety Bond Expiration Period No definition available.
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- Definition The current carrying amount of the liability for the freestanding or embedded guarantor's obligations under the guarantee or each group of similar guarantees. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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| X | ||||||||||
- Definition The total amount of the contingent obligation under letters of credit outstanding as of the reporting date. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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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 of loss contingency liability. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of receivable related to a loss contingency accrual. For example, an insurance recovery receivable. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Details
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