v3.25.3

Property and Equipment - Schedule of Property and Equipment, at Cost (Details) - USD ($) $ in Thousands	Sep. 30, 2025	Sep. 30, 2024
Property and equipment
Total	$ 1,141,600	$ 1,061,200
Accumulated depreciation and amortization	(725,400)	(706,800)
Property and equipment, net	416,164	354,377
Building and land
Property and equipment
Total	$ 10,500	10,100
Building and land \| Minimum
Property and equipment
Useful Lives (years)	10 years
Building and land \| Maximum
Property and equipment
Useful Lives (years)	45 years
Leasehold improvements
Property and equipment
Total	$ 275,000	299,300
Leasehold improvements \| Minimum
Property and equipment
Useful Lives (years)	1 year
Leasehold improvements \| Maximum
Property and equipment
Useful Lives (years)	20 years
Computer systems and equipment
Property and equipment
Total	$ 770,400	659,600
Computer systems and equipment \| Minimum
Property and equipment
Useful Lives (years)	3 years
Computer systems and equipment \| Maximum
Property and equipment
Useful Lives (years)	12 years
Furniture and fixtures
Property and equipment
Total	$ 85,700	$ 92,200
Furniture and fixtures \| Minimum
Property and equipment
Useful Lives (years)	3 years
Furniture and fixtures \| Maximum
Property and equipment
Useful Lives (years)	10 years

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

+ References

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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

+ References

No definition available.

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AECOM 10-K