Revenue and Contract Balances - Disaggregation of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended
Dec. 29, 2024	Dec. 31, 2023
Disaggregation of Revenue [Line Items]
Revenue	$ 1,420,561	$ 1,228,267
Fixed-price
Disaggregation of Revenue [Line Items]
Revenue	519,822	471,442
Time-and-materials
Disaggregation of Revenue [Line Items]
Revenue	598,948	549,651
Cost-plus
Disaggregation of Revenue [Line Items]
Revenue	301,791	207,174
U.S. federal government
Disaggregation of Revenue [Line Items]
Revenue	501,848	382,076
U.S. state and local government
Disaggregation of Revenue [Line Items]
Revenue	202,987	150,925
U.S. commercial
Disaggregation of Revenue [Line Items]
Revenue	233,591	222,430
International
Disaggregation of Revenue [Line Items]
Revenue	$ 482,135	$ 472,836

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

+ References

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+ Details