Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2026	Mar. 31, 2025
Statement of Comprehensive Income [Abstract]
Net income including noncontrolling interests	$ 65,211	$ 81,787
Other comprehensive income, net of tax
Foreign currency translation adjustment, net of tax	(2,517)	847
Pension adjustments, net of tax	0	7
Comprehensive income including noncontrolling interests, net of tax	62,694	82,641
Comprehensive income attributable to noncontrolling interests, net of tax	(12,285)	(15,584)
Comprehensive income attributable to Parsons Corporation, net of tax	$ 50,409	$ 67,057

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income (loss) and other comprehensive income (loss), attributable to noncontrolling interests. Excludes changes in equity resulting from investments by owners and distributions to owners.

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- Definition

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income. Excludes changes in equity resulting from investments by owners and distributions to owners.

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- Definition

The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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