v3.25.0.1
Quarterly Information - Unaudited - Schedule of Selected Quarterly Financial Information (Parenthetical) (Details) - USD ($)
shares in Thousands, $ in Thousands
 3 Months Ended 12 Months Ended
Jan. 01, 2024
Mar. 31, 2024
Dec. 31, 2024
Dec. 31, 2023
Dec. 31, 2022
Quarterly Financial Information Disclosure [Abstract]          
Accounting Standards Update [Extensible Enumeration] Accounting Standards Update 2024-04 [Member]        
Reversal of loss on extinguishment of debt $ 211,000 $ 211,000      
Reversal of tax benefit of loss on extinguishment of debt 49,900 49,900      
Convertible debt repurchase loss 18,400 18,355 $ 18,355 $ 0 $ 0
Increase in shareholders equity relating to reversal of loss on extinguishment of debt and inducement expenses 192,600   192,600    
Adjustments to shareholders equity relating to reversal of tax benefit 45,600   45,600    
Convertible senior notes if-converted method interest adjustment $ 2,800   $ 2,932 $ 2,291 $ 2,176
Dilutive effect of stock-based awards 1,500   1,778 1,173 808
Dilutive effect of convertible senior notes 6,800   3,628 8,917 8,917
Diluted net income attributable to Parsons Corporation   $ 42,500 $ 237,985 $ 163,440 $ 98,840
Diluted shares   114,400 112,174 115,082 113,483