Other liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Other Liabilities Disclosure [Abstract]
General trade and overhead liabilities	$ 588,733	$ 524,981	$ 463,882
Personnel related liabilities	240,222	218,574	378,251
Operating lease liabilities	36,282	36,783	36,414
Facility related liabilities	$ 8,033	8,547	11,078
Government Assistance, Liability, Current, Statement of Financial Position [Extensible Enumeration]	Total
Other liabilities	$ 21,098	91,730	13,532
Restructuring liabilities	10,383	29,120	4,951
Short term government grants	75	41	43
Total	904,826	909,776	908,151
Amounts due to third parties for reimbursable expenses	$ 427,100	$ 369,200	$ 333,000

Other Liabilities, Amount Payable To Third Parties For Reimbursable Expenses

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- Definition

Restructuring Reserve And Other Liabilities, Current

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Carrying value as of the balance sheet date of obligations incurred through that date and payable for utilities, such as electrical power, heating oil, natural gas, and water. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Total of the carrying values as of the balance sheet date of obligations incurred through that date and payable for obligations related to services received from employees, such as accrued salaries and bonuses, payroll taxes and fringe benefits. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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- Definition

Amount of liability from government assistance, classified as current.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 832
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
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-Publisher FASB
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Indicates line item in statement of financial position that includes liability from government assistance, classified as current.

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Present value of lessee's discounted obligation for lease payments from operating lease, classified as current.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479041/842-20-45-1

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Amount of expenses incurred but not yet paid classified as other, due within one year or the normal operating cycle, if longer.

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Amount of liabilities classified as other, due within one year or the normal operating cycle, if longer.

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-Topic 210
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Obligations not otherwise itemized or categorized in the footnotes to the financial statements that are due within one year or operating cycle, if longer, from the balance sheet date.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Section S99
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