Discontinued operations - Schedule of Income and Expense Constituting Pretax Income (Loss) From Discontinued Operations (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Discontinued operations, net of tax	$ (397)	$ 40,194	$ (899)	$ 66,357
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	703,074	0	1,328,624
Operating expenses	429	653,063	1,028	1,239,322
Operating (loss) income	(429)	50,011	(1,028)	89,302
Other income	0	4,298	0	6,176
Interest expense	0	2,108	0	4,303
(Loss) income from discontinued operations before income taxes	(429)	52,201	(1,028)	91,175
Income tax (benefit) expense	(32)	12,007	(129)	24,818
Discontinued operations, net of tax	$ (397)	$ 40,194	$ (899)	$ 66,357