Segment Information - Summary of Business Segment Information (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021
Segment Reporting Information [Line Items]
Total revenue	$ 949,069	$ 874,697
Federal Solution Segment
Segment Reporting Information [Line Items]
Total revenue	491,629	452,069
Critical Infrastructure
Segment Reporting Information [Line Items]
Total revenue	$ 457,440	$ 422,628

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.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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+ Details