Summary of Employee Stock Options Activity (Detail) (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
Sep. 30, 2014
Stock Based Compensation Activity [Line Items]
Balance as of September 30, 2013, Number of Optioned Shares	93,400
Exercised, Number of Optioned Shares	(1,750)
Forfeited, Number of Optioned Shares	(500)
Balance as of September 30, 2014, Number of Optioned Shares	91,150
Exercisable as of September 30, 2014, Number of Optioned Shares	91,150
Balance as of September 30, 2013, Weighted Average Exercise Price	$ 18.91
Exercised, Weighted Average Exercise Price	$ 18.91
Forfeited, Weighted Average Exercise Price	$ 18.91
Balance as of September 30, 2014, Weighted Average Exercise Price	$ 18.91
Exercisable as of September 30, 2014, Weighted Average Exercise Price	$ 18.91
Balance as of September 30, 2014, Weighted Average Remaining Contractual Term in Years	4 years 2 months 1 day
Exercisable as of September 30, 2014, Weighted Average Remaining Contractual Term in Years	4 years 2 months 1 day
Balance as of September 30, 2014, Aggregate Intrinsic Value	$ 0
Exercisable as of September 30, 2014, Aggregate Intrinsic Value	$ 0

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

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-Section 50

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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Number of options outstanding, including both vested and non-vested options.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

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Number of share options (or share units) exercised during the current period.

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