Additional Financial Information - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended	12 Months Ended	10 Months Ended
Sep. 30, 2011 Successor [Member]	Sep. 30, 2013 Successor [Member]	Sep. 30, 2012 Successor [Member]	Jul. 19, 2011 Predecessor [Member]
Supplemental Cash Flow Information [Line Items]
Interest payments	$ 34	$ 206	$ 193	$ 176
Income and withholding taxes, net of refunds	9	26	42	19
Settlement of an income tax audit			$ 15

The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income, net of any cash received during the current period as refunds for the overpayment of taxes.

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- Definition

The amount of the additional liability or refund received or expected based on a final settlement with a taxing authority.

+ 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 (c)

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

+ Details

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- Definition

The amount of cash paid for interest during the period.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4297-108586

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 25

-Subparagraph (e)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3536-108585

+ Details

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- Details

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