Share-Based Compensation - 2019 Stock-Based Incentive Compensation Plan (Details) - USD ($)	12 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2017
Share-based compensation.
Common stock, shares authorized	75,000,000	75,000,000
Share-based compensation expense	$ 173,000	$ 200,000	$ 203,000
2019 Plan
Share-based compensation.
Common stock, shares authorized	139,691
Share-based compensation expense	$ 0	$ 0	$ 0
Number of shares of common stock reserved for awards	750,000
Number of shares of common stock available for awards under the plan	889,691
2019 Plan \| Employee
Share-based compensation.
Number of shares of common stock reserved for awards	300,000

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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The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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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.

+ References

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).

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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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