Acquisition of NHUMO - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	1 Months Ended	9 Months Ended
Nov. 30, 2013	Jun. 30, 2014
Business Acquisition [Line Items]
Preferred stock redemption amount		$ 29
Acquisition costs		1
Gain on acquisition		29
Customer Relationships [Member]
Business Acquisition [Line Items]
Intangible asset		57
Amortized period		17 years
NHUMO [Member]
Business Acquisition [Line Items]
Percentage acquisition	60.00%
Ownership percentage prior to acquisition	40.00%
Cash paid on acquisition	80	80
Preferred stock redemption amount	25	28
Dividend percentage of preferred stock	6.00%
Preferred stock issued on acquisition	25
Dividend received from NHUMO	14
Gain on acquisition		29
Previously held equity interest in NHUMO		$ 54

Proceeds from dividend from interest in joint venture.

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- Definition

Percentage of voting equity interests acquired at the acquisition date in the business combination.

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-Publisher FASB

-Name Accounting Standards Codification

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- Definition

This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

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Amount of equity interests of the acquirer, including instruments or interests issued or issuable in consideration for the business combination.

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The amount of identifiable intangible assets recognized as of the acquisition date.

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- Definition

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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Percentage of equity in the acquiree held by the acquirer immediately before the acquisition date in a business combination.

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In a business combination achieved in stages, this element represents the amount of gain recognized by the entity as a result of remeasuring to fair value the equity interest in the acquiree it held before the business combination.

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Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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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-Glossary Investing Activities

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The percentage rate used to calculate dividend payments on preferred stock.

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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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