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Derivative Financial Instruments and Fair Value Measurements (Details) AUD in Millions | 9 Months Ended | 12 Months Ended |  |
--- | --- | --- | --- | ---
Jun. 30, 2017 USD ($) | Sep. 30, 2015 item | Jun. 30, 2017 AUD | Jun. 30, 2017 USD ($) | Sep. 30, 2016 AUD | Sep. 30, 2016 USD ($)
Derivative financial instruments |  |  |  |  |  |
Number of contingent consideration arrangements | item |  | 1 |  |  |  |
Payments |  |  |  | $ 21,000,000 |  |
Level 3 |  |  |  |  |  |
Derivative financial instruments |  |  |  |  |  |
Fair value of contingent consideration liability |  |  |  | 13,000,000 |  | $ 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 21.1 | $ 15,700,000 | AUD 58.6 | $ 43,400,000

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- 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
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- Definition Represents payments under the contingent consideration agreement, including cash and shares. + References No definition available. + Details
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- 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
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- 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
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- 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
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- Definition Fixed interest rate related to the interest rate derivative. + References No definition available. + Details
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- 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=64837297&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
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- 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
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