REVENUE - Revenue by Contract Type (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Disaggregation of Revenue [Line Items]
Total revenue	$ 4,480,038	$ 4,322,155	$ 3,963,126
Cost-plus and cost-reimbursable
Disaggregation of Revenue [Line Items]
Total revenue	2,744,753	2,531,792	2,209,241
Firm-fixed-price
Disaggregation of Revenue [Line Items]
Total revenue	1,609,027	1,675,603	1,626,262
Time-and-materials
Disaggregation of Revenue [Line Items]
Total revenue	$ 126,258	$ 114,760	$ 127,623

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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+ Details

- Definition

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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+ Details