Income Tax Uncertainties - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended
Dec. 31, 2014
Income Taxes [Line Items]
Uncertain tax positions from expirations of statute of limitations	$ 11
Deferred tax assets	$ 5us-gaap_DeferredTaxAssetsNet
Earliest Tax Year [Member] \| U.S. Federal [Member] \| Internal Revenue Service (IRS) [Member]
Income Taxes [Line Items]
Tax years remain subject to examination	2011
Earliest Tax Year [Member] \| State Tax Authorities [Member]
Income Taxes [Line Items]
Tax years remain subject to examination	2005
Earliest Tax Year [Member] \| Non-U.S. Jurisdictions [Member]
Income Taxes [Line Items]
Tax years remain subject to examination	2004
Latest Tax Year [Member] \| U.S. Federal [Member] \| Internal Revenue Service (IRS) [Member]
Income Taxes [Line Items]
Tax years remain subject to examination	2014
Latest Tax Year [Member] \| State Tax Authorities [Member]
Income Taxes [Line Items]
Tax years remain subject to examination	2014
Latest Tax Year [Member] \| Non-U.S. Jurisdictions [Member]
Income Taxes [Line Items]
Tax years remain subject to examination	2014

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Amount after allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (b),(c)

-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32537-109319

+ Details

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- Definition

Tax year that remains open to examination under enacted tax laws, in CCYY format.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 15

-Subparagraph (e)

-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32718-109319

+ Details

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- Definition

Amount of decrease in unrecognized tax benefits resulting from lapses of applicable statutes of limitations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 15A

-Subparagraph (a)(4)

-URI http://asc.fasb.org/extlink&oid=6907707&loc=SL6600010-109319

+ Details

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