Discontinued operations - Schedule of Income and Expense Constituting Pretax Income (Loss) From Discontinued Operations (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2025	Mar. 31, 2024
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Discontinued operations, net of tax	$ (502)	$ 26,163
Everus Corporation \| Discontinued Operations, Disposed of by Means Other than Sale, Spinoff
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Operating revenues	0	625,550
Operating expenses	600	586,259
Operating (loss) income	(600)	39,291
Other income	0	1,878
Interest expense	0	2,195
(Loss) income from discontinued operations before income taxes	(600)	38,974
Income tax (benefit) expense	(98)	12,811
Discontinued operations, net of tax	$ (502)	$ 26,163

Amount before tax of income (loss) from a discontinued operation. Includes, but is not limited to, the income (loss) from operations during the phase-out period, gain (loss) on disposal, gain (loss) for reversal of write-down (write-down) to fair value, less cost to sell, and adjustments to a prior period gain (loss) on disposal.

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Amount of tax expense (benefit) related to a discontinued operation. Includes, but is not limited to, tax expense (benefit) related to income (loss) from operations during the phase-out period, tax expense (benefit) related to gain (loss) on disposal, tax expense (benefit) related to gain (loss) for reversal of write-down (write-down) to fair value, less cost to sell, and tax expense (benefit) related to adjustments of a prior period gain (loss) on disposal.

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Amount of interest expense attributable to disposal group, including, but not limited to, discontinued operation.

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Amount of operating expense attributable to disposal group, including, but not limited to, discontinued operation.

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Amount of revenue attributable to disposal group, including, but not limited to, discontinued operation.

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