Subsequent Events	6 Months Ended
Jun. 30, 2024
Subsequent Events [Abstract]
Subsequent Events	19. Subsequent Events After the end of the quarter ended June 30, 2024, the Company entered into a merger agreement to acquire a 100% ownership interest in BlackSignal Technologies, LLC, ("BlackSignal") a privately-owned company, for approximately $200 million from cash on hand. Headquartered in Chantilly, Virginia, BlackSignal is a next-generation digital signal processing, electronic warfare, and cyber security provider built to counter near peer threats. Upon closing, Parsons believes that the acquisition will expand Parsons' customer base across the Department of Defense and Intelligence Community and significantly strengthen Parsons' positioning within offensive cyber warfare, while adding new capabilities in the counterspace radio frequency domain. We anticipate that the closing will occur in Q3 2024.

The entire disclosure for significant events or transactions that occurred after the balance sheet date through the date the financial statements were issued or the date the financial statements were available to be issued. Examples include: the sale of a capital stock issue, purchase of a business, settlement of litigation, catastrophic loss, significant foreign exchange rate changes, loans to insiders or affiliates, and transactions not in the ordinary course of business.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 855
-Name Accounting Standards Codification
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 855
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-Name Accounting Standards Codification
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-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483399/855-10-50-2

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