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Reportable Segments - Summarized financial information (Details) $ in Thousands | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Mar. 31, 2024 USD ($) | Mar. 31, 2023 USD ($) | Mar. 31, 2024 USD ($) segment | Mar. 31, 2023 USD ($) | Sep. 30, 2023 USD ($)
Summarized financial information concerning the Company's reportable segments |  |  |  |  |
Revenue | $ 3,943,833 | $ 3,490,172 | $ 7,843,753 | $ 6,872,527 |
Gross profit | 261,174 | 228,094 | $ 505,144 | 443,082 |
Number of reportable segments | segment |  |  | 3 |  |
Equity in earnings of joint ventures | 19,459 | 7,456 | $ (9,482) | 17,285 |
General and administrative expenses | (44,686) | (34,147) | (80,410) | (69,759) |
Restructuring costs | (35,465) | (3,973) | (51,645) | (41,432) |
Operating income (loss) | 200,482 | 197,430 | 363,607 | 349,176 |
Segment assets | 11,457,393 |  | 11,457,393 |  | $ 11,233,398
Total |  |  |  |  |
Summarized financial information concerning the Company's reportable segments |  |  |  |  |
Revenue | 3,943,900 | 3,490,100 | 7,843,800 | 6,872,500 |
Gross profit | 261,100 | 228,100 | 505,100 | 443,100 |
Equity in earnings of joint ventures | 19,500 | 7,500 | (9,500) | 17,300 |
General and administrative expenses | (44,700) | (34,200) | (80,400) | (69,800) |
Restructuring costs | (35,400) | (3,900) | (51,600) | (41,400) |
Operating income (loss) | $ 200,500 | $ 197,500 | $ 363,600 | $ 349,200 |
Gross profit as a % of revenue | 6.60% | 6.50% | 6.40% | 6.40% |
Operating Segments | Americas |  |  |  |  |
Summarized financial information concerning the Company's reportable segments |  |  |  |  |
Revenue | $ 3,038,600 | $ 2,630,200 | $ 6,077,300 | $ 5,209,500 |
Gross profit | 184,400 | 173,300 | 355,400 | 336,200 |
Equity in earnings of joint ventures | 4,800 | 4,900 | 8,400 | 5,800 |
Operating income (loss) | $ 189,200 | $ 178,200 | $ 363,800 | $ 342,000 |
Gross profit as a % of revenue | 6.10% | 6.60% | 5.80% | 6.50% |
Segment assets | $ 7,754,400 |  | $ 7,754,400 |  | 7,433,100
Operating Segments | International |  |  |  |  |
Summarized financial information concerning the Company's reportable segments |  |  |  |  |
Revenue | 904,800 | $ 859,800 | 1,765,800 | $ 1,662,600 |
Gross profit | 76,200 | 54,700 | 149,000 | 106,500 |
Equity in earnings of joint ventures | 5,000 | 5,400 | 9,300 | 8,700 |
Operating income (loss) | $ 81,200 | $ 60,100 | $ 158,300 | $ 115,200 |
Gross profit as a % of revenue | 8.40% | 6.40% | 8.40% | 6.40% |
Segment assets | $ 2,671,400 |  | $ 2,671,400 |  | 2,536,200
Operating Segments | AECOM Capital |  |  |  |  |
Summarized financial information concerning the Company's reportable segments |  |  |  |  |
Revenue | 500 | $ 100 | 700 | $ 400 |
Gross profit | 500 | 100 | 700 | 400 |
Equity in earnings of joint ventures | 9,700 | (2,800) | (27,200) | 2,800 |
General and administrative expenses | (9,700) | (2,900) | (12,100) | (5,600) |
Operating income (loss) | 500 | (5,600) | (38,600) | (2,400) |
Segment assets | 53,200 |  | 53,200 |  | 64,500
Corporate |  |  |  |  |
Summarized financial information concerning the Company's reportable segments |  |  |  |  |
General and administrative expenses | (35,000) | (31,300) | (68,300) | (64,200) |
Restructuring costs | (35,400) | (3,900) | (51,600) | (41,400) |
Operating income (loss) | (70,400) | $ (35,200) | (119,900) | $ (105,600) |
Segment assets | $ 873,300 |  | $ 873,300 |  | $ 1,104,400

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