Segment Information - Summary of Adjusted EBITDA Business Segment Information (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Adjusted EBITDA attributable to Parsons Corporation
Adjusted EBITDA attributable to Parsons Corporation	$ 80,505	$ 70,953
Adjusted EBITDA attributable to noncontrolling interests	9,886	3,295
Depreciation and amortization	(28,359)	(30,509)
Interest expense, net	(5,665)	(3,873)
Income tax expense	(11,503)	(8,119)
Equity-based compensation expense	(6,703)	(3,898)
Transaction-related costs	(1,618)	(2,398)
Restructuring expense	(546)	(213)
Other	(721)	(1,395)
Net income including noncontrolling interests	35,276	23,843
Net income attributable to noncontrolling interests	9,723	3,176
Net income attributable to Parsons Corporation	25,553	20,667
Federal Solution Segment
Adjusted EBITDA attributable to Parsons Corporation
Adjusted EBITDA attributable to Parsons Corporation	56,148	42,638
Critical Infrastructure
Adjusted EBITDA attributable to Parsons Corporation
Adjusted EBITDA attributable to Parsons Corporation	$ 24,357	$ 28,315