Restricted Stock Plan and Long Term Incentive Plan (Summary Of Changes In Unvested Shares Of Restricted Stock Awards) (Details) - $ / shares	12 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2019
Market-Based Unvested Restricted Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unvested shares, Beginning balance	61,470	46,670	92,704
Unvested Restricted Shares, Granted	303,750	39,579	43,287
Unvested Restricted Shares, Forfeited	(9,071)	(24,779)	(89,321)
Unvested shares, Ending balance	356,149	61,470	46,670
Weighted Average Grant Date Fair Value, Beginning balance	$ 8.87	$ 10.21	$ 11.00
Weighted Average Grant Date Fair Value, Granted	2.72	8.83	8.24
Weighted Average Grant Date Fair Value, Forfeited	11.34	11.34	10.08
Weighted Average Grant Date Fair Value, Ending balance	$ 3.56	$ 8.87	$ 10.21
Time-Based Unvested Restricted Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unvested shares, Beginning balance	90,522	18,707	28,667
Unvested Restricted Shares, Granted	125,000	102,154	27,978
Unvested Restricted Shares, Vested	(9,860)	(20,410)	(24,785)
Unvested Restricted Shares, Forfeited	(2,562)	(9,929)	(13,153)
Unvested shares, Ending balance	203,100	90,522	18,707
Weighted Average Grant Date Fair Value, Beginning balance	$ 9.49	$ 17.54	$ 20.40
Weighted Average Grant Date Fair Value, Granted	3.17	9.21	15.61
Weighted Average Grant Date Fair Value, Vested	14.08	13.35	18.30
Weighted Average Grant Date Fair Value, Forfeited	13.00	13.93	18.23
Weighted Average Grant Date Fair Value, Ending balance	$ 5.33	$ 9.49	$ 17.54
Performance Based Unvested Restricted Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unvested shares, Beginning balance	34,814
Unvested Restricted Shares, Granted		39,579
Unvested Restricted Shares, Forfeited		(4,765)
Unvested shares, Ending balance	34,814	34,814

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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)(3)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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- Definition

Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
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-Paragraph 2
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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).

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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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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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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

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The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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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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