Stock-Based Compensation - Additional Information (Detail) (USD $) Share data in Thousands, unless otherwise specified	3 Months Ended
Dec. 31, 2012	Dec. 31, 2011
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average remaining term, options outstanding	2 years 6 months
Aggregate intrinsic value, options outstanding	$ 12
Outstanding share awards earned and issued at greater than the target number of shares	150.00%
2007 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options, vesting period	10 years
Aggregate number of shares that may be awarded	600
Performance period	3 years
Stock options may be awarded	368
Compensation expense related to performance and restricted shares awarded	24,000	239,000
Total unrecognized compensation cost related to performance and restricted shares awarded	$ 1,258,000
Period of recognized compensation cost	2 years 9 months 18 days
2007 Plan \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common shares earned as percentage of initial target number shares awarded	150.00%
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options, vesting period	10 years
Performance shares awarded during fiscal 2012 \| 2007 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense accrued as percentage of target levels	100.00%
Performance shares awarded during fiscal 2011 \| 2007 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense accrued as percentage of target levels		50.00%
Restricted shares \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options, vesting period	1 year
Restricted shares \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options, vesting period	3 years

Common shares earned percentage of initial target number shares awarded.

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Compensation expense accrued percentage of target levels.

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- Definition

Outstanding share awards earned and issued at greater than the target number of shares.

+ References

No definition available.

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- Definition

Share based compensation arrangement by share based payment award performance period.

+ References

No definition available.

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- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

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-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph g(1)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 14

-Section F

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Aggregate unrecognized cost of share-based awards, other than options, made to employees under an equity-based compensation plan, that have yet to vest.

+ References

No definition available.

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph a

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Publisher FASB

-Name Accounting Standards Codification

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- Definition

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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- Definition

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

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

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-Paragraph A240

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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- Definition

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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