v3.26.1
Goodwill and Intangible Assets - Summary of Gross Amount and Accumulated Amortization of Acquired Finite-lived Intangibles (Details) - USD ($)
$ in Thousands
 6 Months Ended
Mar. 29, 2026
Sep. 28, 2025
Finite-Lived Intangible Assets [Line Items]    
Gross Amount $ 272,817 $ 248,531
Accumulated Amortization (143,532) (127,371)
Net Amount $ 129,285 121,160
Client relations    
Finite-Lived Intangible Assets [Line Items]    
Weighted- Average Remaining Life (in Years) 6 years 9 months 18 days  
Gross Amount $ 188,191 169,807
Accumulated Amortization (65,993) (56,241)
Net Amount $ 122,198 113,566
Backlog    
Finite-Lived Intangible Assets [Line Items]    
Weighted- Average Remaining Life (in Years) 8 months 12 days  
Gross Amount $ 50,190 43,919
Accumulated Amortization (43,619) (40,397)
Net Amount $ 6,571 3,522
Trade names    
Finite-Lived Intangible Assets [Line Items]    
Weighted- Average Remaining Life (in Years) 3 months 18 days  
Gross Amount $ 34,436 34,805
Accumulated Amortization (33,920) (30,733)
Net Amount $ 516 $ 4,072