Stock-Based Compensation (Details) $ / shares in Units, $ in Thousands	3 Months Ended
Dec. 31, 2018 USD ($) tranche $ / shares shares	Dec. 31, 2017 USD ($)
Schedule Of Earnings Per Share Basic And Diluted [Line Items]
Outstanding share awards earned and issued at greater than the target number of shares	200.00%
2016 Plan
Schedule Of Earnings Per Share Basic And Diluted [Line Items]
Aggregate number of shares that may be awarded (in shares)	646,000
Exercise period for shares awarded under plan	10 years
Number of tranches in award \| tranche	2
Outstanding share awards that may be awarded (in shares)	170,000
Share-based compensation expense (benefit) \| $	$ 236	$ 194
Total unrecognized compensation cost related to performance and restricted shares \| $	$ 1,133
Period of recognized compensation cost (in years)	1 year 8 months
2016 Plan \| Performance shares
Schedule Of Earnings Per Share Basic And Diluted [Line Items]
Performance period (in years)	3 years
Shares granted in period (in shares)	87,000
Shares forfeited in period (in shares)	1,000
2016 Plan \| Performance shares \| Minimum
Schedule Of Earnings Per Share Basic And Diluted [Line Items]
Common shares earned pursuant to award (in shares)	0
2016 Plan \| Performance shares \| Maximum
Schedule Of Earnings Per Share Basic And Diluted [Line Items]
Common shares earned as percentage of initial target number shares awarded	200.00%
2016 Plan \| Performance and Restricted Shares
Schedule Of Earnings Per Share Basic And Diluted [Line Items]
Shares granted in period (in shares)	134,000
Shares granted in period, grant date fair value (in dollars per share) \| $ / shares	$ 4.73
Vesting period (in years)	3 years
2016 Plan \| Restricted Stock
Schedule Of Earnings Per Share Basic And Diluted [Line Items]
Shares granted in period (in shares)	47,000
2016 Plan \| Restricted Stock \| Minimum
Schedule Of Earnings Per Share Basic And Diluted [Line Items]
Vesting period (in years)	1 year
2016 Plan \| Restricted Stock \| Maximum
Schedule Of Earnings Per Share Basic And Diluted [Line Items]
Vesting period (in years)	3 years

Common shares earned percentage of initial target number shares awarded.

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Common shares earned pursuant to award.

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

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Share Based Compensation, Number Of Tranches

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Share-based Compensation Arrangement by Share-based Payment Award, Qualifying for the Award Period

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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.

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

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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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The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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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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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).

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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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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.

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