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Goodwill - Narrative (Details) - USD ($) $ in Thousands |  |  | 6 Months Ended | 12 Months Ended |
--- | --- | --- | --- | --- | ---
Aug. 19, 2024 | Jan. 09, 2024 | Jun. 30, 2025 | Jun. 30, 2024 | Dec. 31, 2024 | Dec. 31, 2023
Goodwill and Intangible Assets Disclosure [Abstract] |  |  |  |  |  |
Goodwill, impairment loss |  |  | $ 0 |  | $ 0 |
Goodwill [Line Items] |  |  |  |  |  |
Purchase of subsidiary undertakings (net of cash acquired) |  |  | 2,537 | $ 7,831 |  |
Goodwill |  |  | 9,092,410 |  | $ 9,051,410 | $ 9,022,075
KCR S.A Group |  |  |  |  |  |
Goodwill [Line Items] |  |  |  |  |  |
Business combination, consideration transferred | $ 92,500 |  |  |  |  |
Purchase of subsidiary undertakings (net of cash acquired) |  |  | 1,300 |  |  |
Goodwill | 43,400 |  |  |  |  |
Intangible assets acquired | 45,100 |  |  |  |  |
KCR S.A Group | Customer relationships |  |  |  |  |  |
Goodwill [Line Items] |  |  |  |  |  |
Intangible assets acquired | 41,400 |  |  |  |  |
KCR S.A Group | Order backlog |  |  |  |  |  |
Goodwill [Line Items] |  |  |  |  |  |
Intangible assets acquired | $ 3,700 |  |  |  |  |
HumanFirst Inc |  |  |  |  |  |
Goodwill [Line Items] |  |  |  |  |  |
Business combination, consideration transferred |  | $ 13,300 |  |  |  |
Purchase of subsidiary undertakings (net of cash acquired) |  |  | $ 1,200 |  |  |
Goodwill |  | 2,700 |  |  |  |
Intangible assets acquired |  | $ 9,900 |  |  |  |

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