Stock Plans - Stock Option Activity (Detail) (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
Sep. 30, 2013
Number of Stock Options
Options outstanding at beginning of period (shares)	193,182
Exercised	(8,600)
Forfeited/expired	(169,042)
Options outstanding at end of period (shares)	15,540
Vested at end of year	15,540
Options exercisable at end of period (shares)	15,540
Options available for future grant	3,259,558
Weighted-Average Remaining Contractual Term
Options outstanding at end of period	9 months
Vested at end of period	9 months
Options exercisable at end of period	9 months
Weighted Average Exercise Price
Options outstanding at beginning of period (USD per share)	$ 13.11
Exercised (USD per share)	$ 7.75
Forfeited/expired (USD per share)	$ 13.13
Options outstanding at end of year (USD per share)	$ 15.86
Vested at end of period (USD per share)	$ 15.86
Options exercisable at end of period (USD per share)	$ 15.86
Aggregate Intrinsic Value
Options outstanding at end of period	$ 0
Vested at end of period	0
Options exercisable at end of period	$ 0

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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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.

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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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For presentations that combine terminations, 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 or that expired.

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Weighted average price of options that were either forfeited or expired.

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The number of shares reserved for issuance under stock option agreements awarded under the plan that validly exist and are outstanding as of the balance sheet date, including 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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The number of exercisable share options (fully vested and expected to vest) that may be converted as of the balance sheet date.

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

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