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Discontinued operations - Narrative (Details) $ in Thousands |  | 3 Months Ended | 9 Months Ended
--- | --- | --- | ---
Oct. 31, 2024 | Sep. 30, 2025 USD ($) | Sep. 30, 2024 USD ($) | Sep. 30, 2025 USD ($) | Sep. 30, 2024 USD ($)
Minimum |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |
Transition services period |  |  |  | 18 months |
Maximum |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |
Transition services period |  |  |  | 2 years |
Discontinued Operations, Disposed of by Means Other than Sale, Spinoff | Everus |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |
Stock split, conversion ratio | 0.25 |  |  |  |
Separation related costs |  | $ 39 | $ 1,900 | $ 586 | $ 9,200
Discontinued Operations, Disposed of by Means Other than Sale, Spinoff | Everus | Cash Received, TSA |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |
Discontinued operation, amount of continuing cash flows after disposal |  | 1,300 |  | 6,800 |
Discontinued Operations, Disposed of by Means Other than Sale, Spinoff | Everus | Cash Paid, TSA |  |  |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |  |  |
Discontinued operation, amount of continuing cash flows after disposal |  | $ 17 |  | $ 42 |

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