Contracts with Customers - Summary of Disaggregation of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Disaggregation Of Revenue [Line Items]
Revenues	$ 1,008,721	$ 879,356	$ 1,957,790	$ 1,754,053
Fixed-Price
Disaggregation Of Revenue [Line Items]
Revenues	279,408	233,231	519,982	463,173
Time-and-Materials
Disaggregation Of Revenue [Line Items]
Revenues	271,330	253,365	534,645	493,030
Cost-Plus
Disaggregation Of Revenue [Line Items]
Revenues	$ 457,983	$ 392,760	$ 903,163	$ 797,850