Contingencies - Additional Information (Details)		3 Months Ended
	Nov. 28, 2023 USD ($)	Mar. 31, 2024 USD ($) Claim
Legal Proceedings [Line Items]
Number of claims outstanding | Claim		0
Alleged Violation of False Claims, Act
Legal Proceedings [Line Items]
Amount paid by relator to acquire vehicles for contractor defendant to perform security services		$ 2,900,000
Alleged Violation of False Claims, Act | Parsons Transportation Group, Inc. and against Alstom Signaling Operations LLC
Legal Proceedings [Line Items]
Award of damages in the total amount	$ 102,500,000
Amount relating to claims assigned	62,500,000
Amount attributable to contractual and indemnification claims	$ 40,000,000
Alleged Violation of False Claims, Act | Minimum
Legal Proceedings [Line Items]
Amount paid per month to contractor defendant by relator on false claims		1,000,000
Loss contingency sought value, civil penalty for each alleged violation of Act		5,500
Alleged Violation of False Claims, Act | Maximum
Legal Proceedings [Line Items]
Loss contingency sought value, civil penalty for each alleged violation of Act		$ 11,000