Acquisition of NHUMO - Components and Allocation of Purchase Price (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended
Dec. 31, 2014	Oct. 31, 2013	Sep. 30, 2014
Assets
Goodwill	$ 524us-gaap_Goodwill		$ 536us-gaap_Goodwill
Liabilities
Fair value of redeemable preferred stock	28us-gaap_PreferredStockRedemptionAmount		27us-gaap_PreferredStockRedemptionAmount
NHUMO [Member]
Assets
Current assets		54	54
Property, plant and equipment		48	48
Other non-current assets		1	1
Intangible assets		57	63
Goodwill		51	45
Total assets acquired		211	211
Liabilities
Accounts payable, accruals and other liabilities		(18)	(20)
Deferred tax liabilities - long-term		(31)	(29)
Total liabilities assumed		(49)	(49)
Net assets acquired		162	162
Cash consideration paid		80
Fair value of redeemable preferred stock		28
Previously held equity interest in NHUMO	54	54
Total		162
NHUMO [Member] \| Measurement Period Adjustments [Member]
Assets
Intangible assets			6
Goodwill			(6)
Liabilities
Accounts payable, accruals and other liabilities			(2)
Deferred tax liabilities - long-term			$ 2

Amount of assets acquired at the acquisition date.

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Amount of assets that are expected to be realized or consumed within one year or the normal operating cycle, if longer, acquired at the acquisition date.

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Amount of liabilities incurred for goods and services received that are used in an entity's business and related party payables, assumed at the acquisition date.

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Amount of deferred tax liability attributable to taxable temporary differences due after one year or the normal operating cycle, if longer, assumed at the acquisition date.

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Amount of intangible assets, excluding goodwill, acquired at the acquisition date.

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Amount of liabilities assumed at the acquisition date.

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Amount recognized as of the acquisition date for the identifiable assets acquired in excess of (less than) the aggregate liabilities assumed.

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Amount of other assets expected to be realized or consumed after one year or the normal operating cycle, if longer, acquired at the acquisition date.

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The amount of property, plant, and equipment recognized as of the acquisition date.

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Amount recognized for assets, including goodwill, in excess of (less than) the aggregate liabilities assumed.

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Fair value at acquisition-date of the equity interest in the acquiree held by the acquirer, immediately before the acquisition date for businesses combined in stages.

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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The redemption (or callable) amount of currently redeemable preferred stock. Includes amounts representing dividends not currently declared or paid but which will be payable under the redemption features or for which ultimate payment is solely within the control of the issuer.

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