{
 "company": "AECOM",
 "ticker": "ACM",
 "cik": 868857,
 "unit": "USD millions",
 "fiscal_year_end_month": 9,
 "as_of": "2026-08-11",
 "generated": "2026-10-31",
 "source": "SEC EDGAR XBRL companyfacts, https://data.sec.gov/api/xbrl/companyfacts/CIK0000868857.json",
 "definitions": {
  "fcf": "Operating cash flow minus purchases of property, plant and equipment (capital expenditure), as reported.",
  "derived": "Quarterly values not reported directly (typically Q4, and quarterly cash flow) are derived as the difference between reported year-to-date periods."
 },
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   "sources": [
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   "derived": [
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   "op_margin": 2.1,
   "net_margin": 0.7,
   "fcf_margin": 6.8
  },
  {
   "period_end": "2023-12-31",
   "label": "Q1 FY24",
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   "fcf": 86.8,
   "sources": [
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   "derived": [],
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   "net_margin": 2.4,
   "fcf_margin": 2.2
  },
  {
   "period_end": "2024-03-31",
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   "sources": [
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   "derived": [
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   "op_margin": 5.1,
   "net_margin": 0.0,
   "fcf_margin": 1.9
  },
  {
   "period_end": "2024-06-30",
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   "sources": [
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   "derived": [],
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   "sources": [
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   "op_margin": 6.8,
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  {
   "period_end": "2025-06-30",
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   "sources": [
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  {
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  {
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   "derived": [],
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 ],
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   "sources": [
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  {
   "period_end": "2023-09-30",
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   "sources": [
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   "derived": [],
   "op_margin": 2.3,
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  {
   "period_end": "2024-09-30",
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   "op_margin": 5.1,
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 ]
}