XML 53 R27.htm IDEA: XBRL DOCUMENT v3.20.2

Major Clients	12 Months Ended
	Sep. 30, 2020
Major Clients
Major Clients	20.         Major Clients No single client accounted for 10% or more of the Company’s revenue in any of the past five fiscal years. Approximately 8%, 9%, and 8% of the Company’s revenue was derived through direct contracts with agencies of the U.S. federal government in the years ended September 30, 2020, 2019 and 2018, respectively.

X

- Definition

The entire disclosure for concentration risk on revenues from major clients. Major clients are those which that the loss of such client would have a material adverse effect on the entity.

+ References

No definition available.

+ Details

Name:	acm_ConcentrationRiskMajorClientsTextBlock
Namespace Prefix:	acm_
Data Type:	nonnum:textBlockItemType
Balance Type:	na
Period Type:	duration

X

- Definition

n/a

+ References

No definition available.

+ Details

Name:	acm_MajorClientsDisclosureAbstract
Namespace Prefix:	acm_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration