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Reportable Segments and Geographic Information - Summarized financial information (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Sep. 30, 2023 | Sep. 30, 2022 | Sep. 30, 2021
Summarized financial information concerning the Company's reportable segments |  |  |
Revenue | $ 14,378,461 | $ 13,148,182 | $ 13,340,852
Gross profit | 945,465 | 847,974 | 798,421
Equity in earnings of joint ventures | (279,352) | 53,640 | 35,044
General and administrative expenses | (153,575) | (147,309) | (155,072)
Restructuring costs | (188,404) | (107,501) | (48,840)
Operating income | 324,134 | 646,804 | 629,553
Segment assets | 11,233,398 | 11,139,315 |
Total |  |  |
Summarized financial information concerning the Company's reportable segments |  |  |
Revenue | 14,378,500 | 13,148,200 | 13,340,900
Gross profit | 945,500 | 848,000 | 798,400
Equity in earnings of joint ventures | (279,400) | 53,600 | 35,000
General and administrative expenses | (153,600) | (147,300) | (155,000)
Restructuring costs | (188,400) | (107,500) | (48,800)
Operating income | $ 324,100 | $ 646,800 | $ 629,600
Gross profit as a % of revenue | 6.60% | 6.40% | 6.00%
Operating Segments | Americas |  |  |
Summarized financial information concerning the Company's reportable segments |  |  |
Revenue | $ 10,975,700 | $ 9,939,300 | $ 10,226,300
Gross profit | 699,700 | 639,900 | 631,600
Equity in earnings of joint ventures | 14,900 | 13,900 | 11,400
Operating income | 714,600 | 653,800 | 643,000
Segment assets | $ 7,433,100 | $ 7,232,200 | $ 7,204,600
Gross profit as a % of revenue | 6.40% | 6.40% | 6.20%
Operating Segments | International |  |  |
Summarized financial information concerning the Company's reportable segments |  |  |
Revenue | $ 3,402,100 | $ 3,206,700 | $ 3,112,600
Gross profit | 245,100 | 205,900 | 164,800
Equity in earnings of joint ventures | 9,600 | 15,300 | 12,200
Operating income | 254,700 | 221,200 | 177,000
Segment assets | $ 2,536,200 | $ 2,467,900 | $ 2,764,500
Gross profit as a % of revenue | 7.20% | 6.40% | 5.30%
Operating Segments | AECOM Capital |  |  |
Summarized financial information concerning the Company's reportable segments |  |  |
Revenue | $ 700 | $ 2,200 | $ 2,000
Gross profit | 700 | 2,200 | 2,000
Equity in earnings of joint ventures | (303,900) | 24,400 | 11,400
General and administrative expenses | (12,600) | (12,600) | (11,100)
Operating income | (315,800) | 14,000 | 2,300
Segment assets | 64,500 | 264,900 | 234,600
Corporate |  |  |
Summarized financial information concerning the Company's reportable segments |  |  |
General and administrative expenses | (141,000) | (134,700) | (143,900)
Restructuring costs | (188,400) | (107,500) | (48,800)
Operating income | (329,400) | (242,200) | (192,700)
Segment assets | $ 1,104,400 | $ 1,095,300 | $ 1,390,900

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