v3.25.4

Revenue Recognition (Tables) | 3 Months Ended
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Dec. 31, 2025
Revenue from Contract with Customer [Abstract] |
Schedule of Revenues Disaggregated by Revenue Sources | The following tables present the Company’s revenues disaggregated by revenue sources:
| Three Months Ended |  |  |  |  |  |
| December 31, 2025 |  | December 31, 2024 |  |  |  |  |  |  |  |
| (in millions) |  |  |  |
Cost reimbursable | $ | 1,598.5 |  |  | $ | 1,505.7 |  |  |  |  |  |  |  |  |
Guaranteed maximum price | 1,350.2 |  |  | 1,527.4 |  |  |  |  |  |  |  |  |
Fixed-price | 882.1 |  |  | 981.1 |  |  |  |  |  |  |  |  |
Total revenue | $ | 3,830.8 |  |  | $ | 4,014.2 |  |  |  |  |  |  |  |  |
| Three Months Ended |  |  |  |  |
| December 31, 2025 |  | December 31, 2024 |  |  |  |  |  |  |
| (in millions) |  |  |
Americas | $ | 2,977.2 |  |  | $ | 3,112.1 |  |  |  |  |  |  |  |
Europe, Middle East, India, Africa | 522.4 |  |  | 537.0 |  |  |  |  |  |  |  |
Asia-Australia-Pacific | 331.2 |  |  | 365.1 |  |  |  |  |  |  |  |
Total revenue | $ | 3,830.8 |  |  | $ | 4,014.2 |  |  |  |  |  |  |  |
Schedule of Net Accounts Receivable | Net accounts receivable consisted of the following:
| December 31, 2025 |  | September 30, 2025
| (in millions)
Billed | $ | 1,755.8 |  |  | $ | 1,934.3 |
Contract retentions | 680.5 |  |  | 647.6 |
Total accounts receivable—gross | 2,436.3 |  |  | 2,581.9 |
Allowance for doubtful accounts and credit losses | (87.9) |  |  | (84.8) |
Total accounts receivable—net | $ | 2,348.4 |  |  | $ | 2,497.1 |

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- Definition Tabular disclosure of disaggregation of revenue into categories depicting how nature, amount, timing, and uncertainty of revenue and cash flows are affected by economic factor. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 606 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 5 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479806/606-10-50-5 + Details
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- Definition Tabular disclosure of the various types of trade accounts and notes receivable and for each the gross carrying value, allowance, and net carrying value as of the balance sheet date. Presentation is categorized by current, noncurrent and unclassified receivables. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 210 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(4)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 210 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(3)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1 + Details
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