Segment Information - Summary of Revenues by Business Lines (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Segment Reporting Information [Line Items]
Revenues	$ 1,008,721	$ 879,356	$ 1,957,790	$ 1,754,053
Federal Solution Segment
Segment Reporting Information [Line Items]
Revenues	537,556	442,675	1,029,185	894,744
Federal Solution Segment | Defense And Intelligence
Segment Reporting Information [Line Items]
Revenues	350,298	297,447	685,825	596,964
Federal Solution Segment | Engineered Systems
Segment Reporting Information [Line Items]
Revenues	187,258	145,228	343,360	297,780
Critical Infrastructure
Segment Reporting Information [Line Items]
Revenues	471,165	436,681	928,605	859,309
Critical Infrastructure | Connected Communities
Segment Reporting Information [Line Items]
Revenues	170,783	140,856	333,437	281,888
Critical Infrastructure | Mobility Solutions
Segment Reporting Information [Line Items]
Revenues	$ 300,382	$ 295,825	$ 595,168	$ 577,421