Stock-Based Compensation - Narrative (Details) - 2007 Plan - USD ($) $ in Thousands	12 Months Ended
Sep. 30, 2019	Sep. 30, 2018
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)	165,000
Outstanding share awards earned and issued at greater than the target number of shares	200.00%
Stock-based compensation expense (benefit)	$ 511	$ 608
Total unrecognized compensation cost related to performance and restricted shares awarded	$ 569
Period of recognized compensation cost	1 year 3 months
Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercise period for performance shares awarded under 2007 Plan	3 years
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
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	200.00%
Restricted shares \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock vesting period	1 year
Restricted shares \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock vesting period	3 years

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Common shares earned pursuant to award.

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Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

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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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