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Reportable Segments and Geographic Information - Summarized financial information (Details) $ in Thousands | 12 Months Ended
--- | ---
Sep. 30, 2024 USD ($) segment | Sep. 30, 2023 USD ($) | Sep. 30, 2022 USD ($)
Summarized financial information concerning the Company's reportable segments |  |  |
Number of reportable segments | segment | 3 |  |
Revenue | $ 16,105,498 | $ 14,378,461 | $ 13,148,182
Gross profit | 1,084,341 | 945,465 | 847,974
Equity in earnings of joint ventures | 2,124 | (279,352) | 53,640
General and administrative expenses | (160,105) | (153,575) | (147,309)
Restructuring costs | (98,918) | (188,404) | (107,501)
Operating income | 827,442 | 324,134 | 646,804
Segment assets | 12,061,669 | 11,233,398 |
Total |  |  |
Summarized financial information concerning the Company's reportable segments |  |  |
Revenue | 16,105,500 | 14,378,500 | 13,148,200
Gross profit | 1,084,300 | 945,500 | 848,000
Equity in earnings of joint ventures | 2,100 | (279,400) | 53,600
General and administrative expenses | (160,100) | (153,600) | (147,300)
Restructuring costs | (98,900) | (188,400) | (107,500)
Operating income | $ 827,400 | $ 324,100 | $ 646,800
Gross profit as a % of revenue | 6.70% | 6.60% | 6.40%
Operating Segments | Americas |  |  |
Summarized financial information concerning the Company's reportable segments |  |  |
Revenue | $ 12,485,700 | $ 10,975,700 | $ 9,939,300
Gross profit | 759,100 | 699,700 | 639,900
Equity in earnings of joint ventures | 15,500 | 14,900 | 13,900
Operating income | 774,600 | 714,600 | 653,800
Segment assets | $ 7,988,100 | $ 7,433,100 | $ 7,232,200
Gross profit as a % of revenue | 6.10% | 6.40% | 6.40%
Operating Segments | International |  |  |
Summarized financial information concerning the Company's reportable segments |  |  |
Revenue | $ 3,618,400 | $ 3,402,100 | $ 3,206,700
Gross profit | 323,800 | 245,100 | 205,900
Equity in earnings of joint ventures | 13,500 | 9,600 | 15,300
Operating income | 337,300 | 254,700 | 221,200
Segment assets | $ 2,734,500 | $ 2,536,200 | $ 2,467,900
Gross profit as a % of revenue | 8.90% | 7.20% | 6.40%
Operating Segments | AECOM Capital |  |  |
Summarized financial information concerning the Company's reportable segments |  |  |
Revenue | $ 1,400 | $ 700 | $ 2,200
Gross profit | 1,400 | 700 | 2,200
Equity in earnings of joint ventures | (26,900) | (303,900) | 24,400
General and administrative expenses | (15,000) | (12,600) | (12,600)
Operating income | (40,500) | (315,800) | 14,000
Segment assets | 53,200 | 64,500 | 264,900
Corporate |  |  |
Summarized financial information concerning the Company's reportable segments |  |  |
General and administrative expenses | (145,100) | (141,000) | (134,700)
Restructuring costs | (98,900) | (188,400) | (107,500)
Operating income | (244,000) | (329,400) | (242,200)
Segment assets | $ 1,208,700 | $ 1,104,400 | $ 1,095,300

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