Annual report pursuant to Section 13 and 15(d)

Goodwill And Intangible Assets - Schedule of goodwill (Details)

v3.24.3
Goodwill And Intangible Assets - Schedule of goodwill (Details) - USD ($)
$ in Thousands
 12 Months Ended
Sep. 30, 2024
Sep. 30, 2023
Sep. 30, 2022
Goodwill [Roll Forward]      
Balance at the beginning of the period $ 1,779,215 $ 1,779,415  
Divestitures (364) (3,172)  
Foreign currency translation 4,020 2,972  
Balance at the end of the period 1,782,871 1,779,215 $ 1,779,415
Goodwill, impairment charges 0 0 0
U.S. Federal Services      
Goodwill [Roll Forward]      
Balance at the beginning of the period 1,559,863 1,559,863  
Divestitures 0 0  
Foreign currency translation 0 0  
Balance at the end of the period 1,559,863 1,559,863 1,559,863
U.S. Services      
Goodwill [Roll Forward]      
Balance at the beginning of the period 164,472 164,472  
Divestitures 0 0  
Foreign currency translation 0 0  
Balance at the end of the period 164,472 164,472 164,472
Outside the U.S.      
Goodwill [Roll Forward]      
Balance at the beginning of the period 54,880 55,080  
Divestitures (364) (3,172)  
Foreign currency translation 4,020 2,972  
Balance at the end of the period $ 58,536 $ 54,880 $ 55,080