Earnings Per Share - Net Income Available to Shareholders to Compute Basic and Diluted EPS (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Earnings Per Share [Abstract]
Net income attributable to Parsons Corporation	$ 25,553	$ 20,667
Convertible senior notes if-converted method interest adjustment	551	540
Diluted net income attributable to Parsons Corporation	$ 26,104	$ 21,207