Segment Information - Summary of Revenues by Business Lines (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Segment Reporting Information [Line Items]
Revenues	$ 949,069	$ 874,697
Federal Solution Segment
Segment Reporting Information [Line Items]
Revenues	491,629	452,069
Federal Solution Segment | Defense And Intelligence
Segment Reporting Information [Line Items]
Revenues	346,233	311,102
Federal Solution Segment | Engineered Systems
Segment Reporting Information [Line Items]
Revenues	145,396	140,967
Critical Infrastructure
Segment Reporting Information [Line Items]
Revenues	457,440	422,628
Critical Infrastructure | Connected Communities
Segment Reporting Information [Line Items]
Revenues	162,654	141,032
Critical Infrastructure | Mobility Solutions
Segment Reporting Information [Line Items]
Revenues	$ 294,786	$ 281,596