Segment Information - Schedule of Segment Revenue, Significant Segment Expenses, and Segment Profit (Details) - USD ($) $ in Thousands		3 Months Ended
		Mar. 31, 2025	Mar. 31, 2024
Segment Reporting Information [Line Items]
Revenue		$ 487,618	$ 494,436
Significant segment expenses:
Direct labor and related fringe costs		191,930	190,023
Subcontractors and other direct costs		110,612	120,510
Indirect and selling expenses		131,891	129,094
Depreciation and amortization		14,795	13,865
Interest expense		7,423	8,329
Provision for income taxes		3,150	7,019
Other segment expense (income)	[1]	966	(1,721)
Net income		26,851	27,317
Depreciation and Amortization
Significant segment expenses:
Depreciation and amortization		5,318	5,574
Amortization of Intangible Assets Acquired in Business Combinations
Significant segment expenses:
Depreciation and amortization		$ 9,477	$ 8,291

[1] Other segment expense (income) includes interest income, foreign currency expense, and gains/losses on disposition of assets.