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Derivatives - Additional Information (Detail) - Cross Currency Swaps [Member] - USD ($) | 9 Months Ended |
--- | --- | ---
Jun. 30, 2018 | Jun. 30, 2017 | Sep. 30, 2017
Prepaid Expenses And Other Asset Current And Other Liabilities [Member] |  |  |
Derivative [Line Items] |  |  |
Fair value of swaps, net liability | $ 17,000,000 |  | $ 13,000,000
Net Investment [Member] |  |  |
Derivative [Line Items] |  |  |
Notional amount | 250,000,000 |  |
Cumulative gain (loss) related to swaps | (15,000,000) |  | $ (9,000,000)
Net cash interest received | $ 2,000,000 | $ 2,000,000 |
Net Investment [Member] | Fixed Rate Debt [Member] |  |  |
Derivative [Line Items] |  |  |
Derivative Instruments Frequency of Cash Settlements | semi-annually |  |

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- Definition Accumulated other comprehensive income (loss) cumulative changes in net gain (loss) from net investment hedges net of tax. + References No definition available. + Details
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- Definition Derivative instruments frequency of cash settlements. + 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 The amount of cash received during the period on settlement of a hedge. + References No definition available. + 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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- Definition Fair value of all derivative liabilities designated as hedges of net investment in foreign operations. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4B -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5624163-113959 + Details
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- Details
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- Details
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