v3.25.4

Discontinued Operations, Goodwill and Intangible Assets - Narrative (Details) $ in Thousands |  |  | 3 Months Ended | 12 Months Ended |  |  |
--- | --- | --- | --- | --- | --- | --- | ---
Jan. 31, 2020 | Dec. 06, 2019 USD ($) | Dec. 31, 2025 USD ($) | Jun. 30, 2025 USD ($) | Dec. 31, 2024 USD ($) | Sep. 30, 2025 USD ($) acquisition | Jun. 30, 2024 USD ($) | Dec. 31, 2014 USD ($) | Feb. 28, 2011 USD ($)
Basis of presentation |  |  |  |  |  |  |  |  |
Non-cash loss on disposal activities |  |  | $ 61,800 |  | $ 0 |  |  |  |
Noncurrent assets held for sale |  |  | 13,953 |  |  | $ 18,953 |  |  |
Amortization expense of acquired intangible assets |  |  | 12,900 |  | $ 1,100 |  |  |  |
2025 Acquisitions |  |  |  |  |  |  |  |  |
Basis of presentation |  |  |  |  |  |  |  |  |
Number of business acquisitions | acquisition |  |  |  |  |  | 2 |  |  |
Total consideration |  |  |  |  |  | $ 375,900 |  |  |
Stock consideration |  |  |  |  |  | 146,400 |  |  |
Task Order, Deactivation Demolition And Removal Service |  |  |  |  |  |  |  |  |
Basis of presentation |  |  |  |  |  |  |  |  |
Percentage of claim recoveries due to purchaser | 10.00% |  |  |  |  |  |  |  |
Percentage of claim recoveries due to seller | 90.00% |  |  |  |  |  |  |  |
Refinery Turnaround Project |  |  |  |  |  |  |  |  |
Basis of presentation |  |  |  |  |  |  |  |  |
Loss from reduction in expected future net cash proceeds |  |  |  | $ 53,000 |  |  |  |  |
Department of Energy | Task Order, Deactivation Demolition And Removal Service |  |  |  |  |  |  |  |  |
Basis of presentation |  |  |  |  |  |  |  |  |
Maximum project cost to pay |  |  |  |  |  |  |  |  | $ 106,000
Additional fees on changed work scope |  | $ 60,400 |  |  |  |  |  | $ 103,000 |
Non-cash loss on disposal activities |  |  | 61,800 |  |  |  |  |  |
Department of Energy | Task Order, Deactivation Demolition And Removal Service | Minimum | Former Affiliate |  |  |  |  |  |  |  |  |
Basis of presentation |  |  |  |  |  |  |  |  |
Damages sought |  | 148,500 |  |  |  |  |  |  |
Department of Energy | Task Order, Deactivation Demolition And Removal Service | Maximum | Former Affiliate |  |  |  |  |  |  |  |  |
Basis of presentation |  |  |  |  |  |  |  |  |
Damages sought |  | $ 329,400 |  |  |  |  |  |  |
Former Affiliate and DOE | Task Order, Deactivation Demolition And Removal Service |  |  |  |  |  |  |  |  |
Basis of presentation |  |  |  |  |  |  |  |  |
Maximum project cost to pay |  |  |  |  |  |  |  |  | 146,000
Minimum project cost to pay |  |  |  |  |  |  |  |  | 106,000
Former Affiliate | Task Order, Deactivation Demolition And Removal Service |  |  |  |  |  |  |  |  |
Basis of presentation |  |  |  |  |  |  |  |  |
Minimum project cost to pay |  |  |  |  |  |  |  |  | $ 146,000
Held for Sale |  |  |  |  |  |  |  |  |
Basis of presentation |  |  |  |  |  |  |  |  |
Equity method investment |  |  | 14,000 |  |  |  |  |  |
Noncurrent assets held for sale |  |  | 14,000 |  |  | $ 19,000 |  |  |
Held for Sale | Revolving Credit Facility |  |  |  |  |  |  |  |  |
Basis of presentation |  |  |  |  |  |  |  |  |
Investment commitment to fund |  |  |  |  |  |  | $ 30,000 |  |
Fund outflow in other investing activities and outstanding |  |  | $ 23,200 |  |  |  |  |  |

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