XML 40 R28.htm IDEA: XBRL DOCUMENT
v3.8.0.1

Derivative Financial Instruments and Fair Value Measurements (Tables) | 3 Months Ended
--- | ---
Dec. 31, 2017
Derivative Financial Instruments and Fair Value Measurements |
Notional principle, fixed rates and related expiration dates of outstanding interest rate swap agreements |
December 31, 2017 |
Notional Amount (in millions) |  | Fixed Rate |  | Expiration Date |
$ | 300.0 |  | 1.63 | % | June 2018 |
300.0 |  | 1.54 | % | September 2018 |
September 30, 2017 |
Notional Amount (in millions) |  | Fixed Rate |  | Expiration Date |
$ | 300.0 |  | 1.63 | % | June 2018 |
300.0 |  | 1.54 | % | September 2018 |

X
- Definition Disclosure information pertaining to derivative instruments and fair value measurements. + References No definition available. + Details
Name: | acm_DerivativeInstrumentHedgingActivitiesAndFairValueMeasurements
Namespace Prefix: | acm_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Tabular disclosure of the notional amounts, fixed rates and related expiration dates of outstanding derivative positions. + References No definition available. + Details
Name: | acm_ScheduleOfNotionalAmountsAndFixedRatesAndExpirationDatesOfOutstandingDerivativePositionsTableTextBlock
Namespace Prefix: | acm_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration