Income Tax - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended
Dec. 31, 2015	Dec. 31, 2014
Income Taxes [Line Items]
(Benefit) Provision for income taxes	$ (5)	$ 3
Effective tax rate	74.00%	5.00%
Net discrete tax (benefits) charges related to tax settlements	$ (6)	$ (13)
Uncertain tax positions from expirations of statute of limitations	$ 2
Earliest Tax Year [Member] \| Internal Revenue Service (IRS) [Member]
Income Taxes [Line Items]
Tax years remain subject to examination	2012
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] \| Internal Revenue Service (IRS) [Member]
Income Taxes [Line Items]
Tax years remain subject to examination	2015
Latest Tax Year [Member] \| State Tax Authorities [Member]
Income Taxes [Line Items]
Tax years remain subject to examination	2015
Latest Tax Year [Member] \| Non-U.S. Jurisdictions [Member]
Income Taxes [Line Items]
Tax years remain subject to examination	2015

Effective income tax rate.

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- Definition

Income taxes.

+ References

No definition available.

+ Details

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- Definition

Net discrete tax benefits charges related to tax settlements.

+ References

No definition available.

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- Definition

Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 9
-Subparagraph (a),(b)
-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32639-109319

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(h))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Income Tax Expense (or Benefit)
-URI http://asc.fasb.org/extlink&oid=6515339

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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

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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

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