v3.25.4

Reportable Segments - Schedule of Financial Information Concerning the Company's Reportable Segments (Details) - USD ($) $ in Thousands | 3 Months Ended
--- | ---
Dec. 31, 2025 | Dec. 31, 2024
Segment Reporting Information [Line Items] |  |
Revenue | $ 3,830,834 | $ 4,014,152
Employee compensation expense | (1,323,100) | (1,275,200)
Equity in earnings of joint ventures | 9,827 | 9,553
Other segment items | (249,500) | (265,900)
Earnings before income taxes and amortization | 288,100 | 269,900
Total |  |
Segment Reporting Information [Line Items] |  |
Subcontractor and other direct costs | (1,979,900) | (2,212,800)
Operating Segments | Americas |  |
Segment Reporting Information [Line Items] |  |
Revenue | 2,977,300 | 3,112,000
Subcontractor and other direct costs | (1,862,600) | (2,061,000)
Employee compensation expense | (756,000) | (708,400)
Equity in earnings of joint ventures | 4,500 | 5,500
Other segment items | (155,600) | (154,600)
Earnings before income taxes and amortization | 207,600 | 193,500
Operating Segments | International |  |
Segment Reporting Information [Line Items] |  |
Revenue | 853,500 | 902,000
Subcontractor and other direct costs | (117,300) | (151,800)
Employee compensation expense | (567,100) | (566,800)
Equity in earnings of joint ventures | 4,600 | 2,900
Other segment items | (92,100) | (108,900)
Earnings before income taxes and amortization | 81,600 | 77,400
Operating Segments | AECOM Capital |  |
Segment Reporting Information [Line Items] |  |
Revenue | 0 | 200
Subcontractor and other direct costs | 0 | 0
Employee compensation expense | 0 | 0
Equity in earnings of joint ventures | 700 | 1,200
Other segment items | (1,800) | (2,400)
Earnings before income taxes and amortization | $ (1,100) | $ (1,000)

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