Accounts receivable, unbilled revenue (contract assets) and unearned revenue or payments on account (contract liabilities) - Schedule of Accounts Receivables and Unbilled Revenue (Details) - USD ($) $ in Thousands |
Sep. 30, 2026 |
Dec. 31, 2025 |
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| Contract Assets [Abstract] | ||
| Accounts receivable (Billed services) | $ 1,550,525 | $ 1,517,217 |
| Allowance for credit losses | (40,480) | (42,319) |
| Accounts receivable net | 1,510,045 | 1,474,898 |
| Unbilled revenue (Unbilled services) | 1,023,170 | 1,096,592 |
| Accounts receivable and unbilled revenue, net | $ 2,533,215 | $ 2,571,490 |
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- Definition Contract Assets No definition available.
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- Definition Contracts Receivable No definition available.
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- Definition Contracts Receivable, Net No definition available.
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- Definition Amount of allowance for credit loss on accounts receivable. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amounts due for billed services rendered or to be rendered, actions taken or to be taken, or a promise to refrain from taking certain actions in accordance with the terms of a legally binding agreement between the Company and, at a minimum, one other party. An example would be amounts billed to customers under contracts or programs but not paid as of the balance sheet date. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount, before allowance for credit loss, of right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time, classified as current. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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