XML 57 R45.htm IDEA: XBRL DOCUMENT
v3.6.0.2

Derivative Financial Instruments and Fair Value Measurements (Details) AUD in Millions | 3 Months Ended | 12 Months Ended |  |
--- | --- | --- | --- | ---
Dec. 31, 2016 USD ($) | Sep. 30, 2015 item | Dec. 31, 2016 AUD | Dec. 31, 2016 USD ($) | Sep. 30, 2016 AUD | Sep. 30, 2016 USD ($)
Derivative financial instruments |  |  |  |  |  |
Number of contingent consideration arrangements | item |  | 1 |  |  |  |
Material subsequent changes in fair value | $ 0 |  |  |  |  |
Level 3 |  |  |  |  |  |
Derivative financial instruments |  |  |  |  |  |
Fair value of contingent consideration liability |  |  |  | $ 22,000,000 |  | $ 39,000,000
Designated as Hedging Instrument | Cash Flow Hedging | Interest rate swap agreements |  |  |  |  |  |
Derivative financial instruments |  |  |  |  |  |
Losses Recognized in Income on Derivatives (Amount Excluded from Effectiveness Testing and Ineffective Portion) | $ 0 |  |  |  |  |
Designated as Hedging Instrument | Cash Flow Hedging | Interest Rate Swap June 2018 |  |  |  |  |  |
Derivative financial instruments |  |  |  |  |  |
Notional Amount |  |  |  | $ 300,000,000 |  | $ 300,000,000
Fixed Rate (as a percent) |  |  | 1.63% | 1.63% | 1.63% | 1.63%
Designated as Hedging Instrument | Cash Flow Hedging | Interest Rate Swap September 2018 |  |  |  |  |  |
Derivative financial instruments |  |  |  |  |  |
Notional Amount |  |  |  | $ 300,000,000 |  | $ 300,000,000
Fixed Rate (as a percent) |  |  | 1.54% | 1.54% | 1.54% | 1.54%
Designated as Hedging Instrument | Cash Flow Hedging | Foreign currency forward contracts |  |  |  |  |  |
Derivative financial instruments |  |  |  |  |  |
Notional principal of derivative exchange contracts |  |  | AUD 44.1 | $ 32,900,000 | AUD 58.6 | $ 43,400,000

X
- Definition Fair value, as of the acquisition date, of potential payments under the contingent consideration arrangement including cash and shares. + References No definition available. + Details
Name: | acm_BusinessAcquisitionFairValueOfContingentConsideration
Namespace Prefix: | acm_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition The number of contingent consideration arrangements entered by the entity in relation to payment of consideration for acquisition in connection with certain financial performance. + References No definition available. + Details
Name: | acm_BusinessCombinationNumberOfContingentConsiderationAgreements
Namespace Prefix: | acm_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition Aggregate notional amount of foreign currency derivatives to exchange foreign currencies. Notional amount refers to the number of currency units specified in the foreign currency derivative contract. + References No definition available. + Details
Name: | acm_NotionalAmountOfForeignCurrencyDerivativeExchangeContracts
Namespace Prefix: | acm_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Aggregate notional amount specified by the derivative(s). Expressed as an absolute value. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Article 12 -Section 13 -Sentence Column B + Details
Name: | invest_DerivativeNotionalAmount
Namespace Prefix: | invest_
Data Type: | xbrli:monetaryItemType
Balance Type: | na
Period Type: | instant

X
- Definition The net increase or decrease in fair value as a result of changes in the assumptions or model used to calculate the fair value of servicing assets. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 860 -SubTopic 50 -Section 50 -Paragraph 3 -Subparagraph (a)(4)(i) -URI http://asc.fasb.org/extlink&oid=56950315&loc=d3e122625-111746 + Details
Name: | us-gaap_AssetAtFairValueChangesInFairValueResultingFromChangesInAssumptions
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Fixed interest rate related to the interest rate derivative. + References No definition available. + Details
Name: | us-gaap_DerivativeFixedInterestRate
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition The portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments representing (a) the amount of the hedge ineffectiveness and (b) the amount, if any, excluded from the assessment of hedge effectiveness. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4C -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5624171-113959 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 25 -Section 50 -Paragraph 1 -Subparagraph (a)(1),(2) -URI http://asc.fasb.org/extlink&oid=6886632&loc=d3e76258-113986 + Details
Name: | us-gaap_DerivativeInstrumentsGainLossRecognizedInIncomeIneffectivePortionAndAmountExcludedFromEffectivenessTestingNet
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition 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. + References No definition available. + Details
Name: | us-gaap_DerivativeLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_FairValueByFairValueHierarchyLevelAxis=us-gaap_FairValueInputsLevel3Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_HedgingDesignationAxis=us-gaap_DesignatedAsHedgingInstrumentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis=us-gaap_CashFlowHedgingMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=us-gaap_InterestRateSwapMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=acm_InterestRateSwapJune2018Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=acm_InterestRateSwapSeptember2018Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=us-gaap_ForeignExchangeForwardMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |