Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Statement of Comprehensive Income [Abstract]
Net income including noncontrolling interests	$ 207,915	$ 126,565	$ 88,952
Other comprehensive income (loss), net of tax
Foreign currency translation adjustment, net of tax	2,375	(7,752)	3,834
Pension adjustments, net of tax	568	(547)	460
Comprehensive income including noncontrolling interests, net of tax	210,858	118,266	93,246
Comprehensive income attributable to noncontrolling interests, net of tax	(46,768)	(29,883)	(24,877)
Comprehensive income attributable to Parsons Corporation, net of tax	$ 164,090	$ 88,383	$ 68,369