The Number of years of capital commitments.

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The amount of the award of the subsequent damages plaintiff seeks in the legal matter.

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Surety bonds issued primarily to support the Company's project execution and insurance program commitments.

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Represents the estimated minimum cost to complete the project and promised amenities.

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The percentage of ownership in joint venture.

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The percentage of post judgment interest rate per year until the date of award is paid.

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The amount of recovery from the refinery owner.

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Amount of funds committed to investment company from investors.

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Amount of damages paid to the plaintiff in the legal matter.

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Amount of receivable related to a loss contingency accrual. For example, an insurance recovery receivable.

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Commitments and Contingencies (Details) - USD ($) $ in Millions						1 Months Ended	9 Months Ended
	Jun. 12, 2019	May 24, 2018	Jul. 21, 2017	Jul. 03, 2017	Apr. 01, 2017	Dec. 31, 2014	Jun. 30, 2019	Apr. 30, 2019	Sep. 02, 2016
Commitments and Contingencies
Damages claimed, value		$ 11.9	$ 81.0	$ 70.0	$ 8.2
Advatech LLC
Commitments and Contingencies
Percentage of ownership in joint venture							60.00%
Advatech LLC \| Genco
Commitments and Contingencies
Damages paid, value	$ 45.8
Invoice amount									$ 81.0
Post-judgment interest rate (as a percent)	9.00%
Department of Energy Deactivation, Demolition, And Removal Project \| Department of Energy \| Maximum
Commitments and Contingencies
Cost-reimbursement at risk							$ 106.0
Department of Energy Deactivation, Demolition, And Removal Project \| AECOM E&C and DOE \| Minimum
Commitments and Contingencies
Cost-reimbursement at risk							106.0
Department of Energy Deactivation, Demolition, And Removal Project \| AECOM E&C and DOE \| Maximum
Commitments and Contingencies
Cost-reimbursement at risk							146.0
Department of Energy Deactivation, Demolition, And Removal Project \| AECOM E&C
Commitments and Contingencies
Claim to DOE, including additional fees						$ 103.0
Possible costs which may exceed contracted amounts						$ 100.0
Department of Energy Deactivation, Demolition, And Removal Project \| AECOM E&C \| Minimum
Commitments and Contingencies
Cost-reimbursement at risk							146.0
Refinery Turnaround Project \| AECOM E&C
Commitments and Contingencies
Damages claimed, value							144.0
Recoverable from refinery owner							90.0
Loss contingency, receivable amount								$ 132.0
AECOM-Canyon Equity Fund, L.P
Commitments and Contingencies
Capital commitments							$ 35.0
Term of capital commitments							10 years
URS \| Design build contractor
Commitments and Contingencies
Subsequent damages claimed, value				$ 103.0
Standby letter of credit
Commitments and Contingencies
Contingency liability							$ 511.2
Surety Bond
Commitments and Contingencies
Surety bonds issued							$ 4,800.0