Equity and Stock-Based Compensation - Summary of Stock Option Transactions and Options Outstanding (Details) - $ / shares	12 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018
Options
Outstanding at end of period	696,665
Stock Options
Options
Outstanding at beginning of period	1,068,665	1,248,758	1,560,441
Granted	32,500	198,850	44,000
Exercised	(160,375)	(52,201)	(277,154)
Forfeited/expired	(244,125)	(326,742)	(78,529)
Outstanding at end of period	696,665	1,068,665	1,248,758
Exercisable at end of period	611,542	842,083	1,014,300
Weighted average grant-date fair value of options granted during the period	$ 2.89	$ 3.08	$ 4.20
Weighted Average Exercise Price
Outstanding at beginning of period	7.04	7.69	7.95
Granted	5.34	5.35	7.40
Exercised	5.47	4.02	6.71
Forfeited/expired	7.94	9.00	16.12
Outstanding at end of period	7.00	7.04	7.69
Exercisable at end of period	$ 7.19	$ 7.45	$ 7.93

The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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For presentations that combine terminations, the number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan or that expired.

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Weighted average price of options that were either forfeited or expired.

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Gross number of share options (or share units) granted during the period.

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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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Number of options outstanding, including both vested and non-vested options.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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Number of share options (or share units) exercised during the current period.

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