Stock-Based Compensation - Narrative (Details) - USD ($)	12 Months Ended
Sep. 30, 2017	Sep. 30, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Outstanding share awards earned and issued at greater than the target number of shares	150.00%
Restricted shares \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock vesting period	3 years
Restricted shares \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock vesting period	1 year
2007 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Aggregate number of shares that may be awarded (in shares)	646,000
Exercise period for shares awarded under 2007 Plan	10 years
Stock options may be awarded (in shares)	413,000
Stock-based compensation expense (benefit)	$ 404,000	$ (474,000)
Income tax benefits resulting from issuance common shares	0	$ 0
Total unrecognized compensation cost related to performance and restricted shares awarded	$ 698,000
Period of recognized compensation cost	1 year 5 months
2007 Plan \| Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercise period for performance shares awarded under 2007 Plan	3 years
2007 Plan \| Performance Shares \| 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%
2007 Plan \| Performance Shares \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Ultimate number of common shares that may be earned (in shares)	0

Common shares earned percentage of initial target number shares awarded.

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Common shares earned pursuant to award.

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Income tax benefits resulting of issuing common shares.

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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, Qualifying for the Award Period

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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 S99
-Paragraph 1
-Subparagraph (SAB Topic 14.F)
-URI http://asc.fasb.org/extlink&oid=27013229&loc=d3e301413-122809

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5047-113901

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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-Section 50
-Paragraph 2
-Subparagraph (h)(1)(i)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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-Paragraph 2
-Subparagraph (i)
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- Definition

Unrecognized cost of unvested share-based awards, other than options, awarded to employees as compensation.

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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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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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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 Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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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.

+ References

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-Publisher FASB
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- Definition

Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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