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v3.25.4

Organization and Basis of Presentation (Details) $ / shares in Units, $ in Millions |  | 1 Months Ended | 12 Months Ended |
--- | --- | --- | --- | ---
Mar. 07, 2025 USD ($) | Nov. 30, 2023 shares | Dec. 31, 2025 USD ($) state reportable_segment $ / shares | Dec. 31, 2024 USD ($) $ / shares | Dec. 31, 2023 USD ($) | May 31, 2023 $ / shares
Organization [Line Items] |  |  |  |  |  |
Number of states in which entity operates | state |  |  | 14 |  |  |
Number of reportable segments | reportable_segment |  |  | 4 |  |  |
Separation transaction, percent of outstanding shares distributed |  |  |  |  |  | 90.00%
Common stock, par value (in dollars per share) | $ / shares |  |  | $ 0.01 | $ 0.01 |  | $ 0.01
Separation transaction, outstanding shares distributed (in shares) | shares |  | 5,656,621 |  |  |  |
Separation transaction, distribution ratio |  |  |  |  |  | 0.25
Reclassification, Other |  |  |  |  |  |
Organization [Line Items] |  |  |  |  |  |
Contract asset |  |  | $ 31.8 |  |  |
Contract liability |  |  | (11.0) |  |  |
Related Party |  |  |  |  |  |
Organization [Line Items] |  |  |  |  |  |
Costs and expenses, related party |  |  | 0.0 | $ 0.0 | $ 10.7 |
Related Party | Selling, General and Administrative Expenses |  |  |  |  |  |
Organization [Line Items] |  |  |  |  |  |
Costs and expenses, related party |  |  |  |  | $ 10.7 |
Knife River |  |  |  |  |  |
Organization [Line Items] |  |  |  |  |  |
Subsidiary, ownership percentage, noncontrolling owner |  |  |  |  |  | 10.00%
Trade Accounts Receivable | Reclassification, Other |  |  |  |  |  |
Organization [Line Items] |  |  |  |  |  |
Retention receivables |  |  | $ 42.8 |  |  |
Strata Corporation |  |  |  |  |  |
Organization [Line Items] |  |  |  |  |  |
Business combination, consideration transferred | $ 454.0 |  |  |  |  |

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