Summary of Combined Activity Under Equity Incentive Plans (Details) - $ / shares	12 Months Ended
Sep. 30, 2020	Sep. 30, 2019
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Outstanding, Number of Nonqualified Options, Beginning Balance	165,600	190,100
Exercised, Number of Nonqualified Options Outstanding		(24,500)
Forfeited, Number of Nonqualified Options Outstanding	(74,500)
Vested, Number of Nonqualified Options Outstanding	0	0
Outstanding, Number of Nonqualified Options, Ending Balance	91,100	165,600
Options, Outstanding, Weighted Average Exercise Price per Share, Beginning Balance	$ 19.15	$ 17.81
Exercised, Weighted Average Exercise Price per Share		8.78
Forfeited, Weighted Average Exercise Price per Share	21.34
Options, Outstanding, Weighted Average Exercise Price per Share, Ending Balance	$ 17.66	$ 19.15
Restricted Stock Awards (RSAs)
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Options, Number of Restricted Stock Awards, Beginning Balance	220,412	327,225
Granted, Number of Restricted Stock Awards		8,000
Forfeited, Number of Restricted Stock Awards	(1,750)	(2,875)
Vested, Number of Restricted Stock Awards	(108,288)	(111,938)
Options, Number of Restricted Stock Awards, Ending Balance	110,374	220,412
Outstanding, Weighted Average Grant-date fair- value per Share, Beginning Balance	$ 16.50	$ 16.42
Granted, Weighted Average Grant-date fair- value per Share		14.59
Forfeited, Weighted Average Grant-date fair- value per Share	17.55	14.60
Vested, Weighted Average Grant-date fair- value per Share	16.32	16.18
Outstanding, Weighted Average Grant-date fair- value per Share, Ending Balance	$ 16.66	$ 16.50
Restricted Stock Units (RSUs)
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Options, Number of Restricted Stock Awards, Beginning Balance	137,290
Granted, Number of Restricted Stock Awards	162,250	161,800
Forfeited, Number of Restricted Stock Awards	(39,560)	(24,010)
Vested, Number of Restricted Stock Awards	(41,723)	(500)
Options, Number of Restricted Stock Awards, Ending Balance	218,257	137,290
Outstanding, Weighted Average Grant-date fair- value per Share, Beginning Balance	$ 15.10
Granted, Weighted Average Grant-date fair- value per Share	14.58	$ 15.11
Forfeited, Weighted Average Grant-date fair- value per Share	14.78	15.17
Vested, Weighted Average Grant-date fair- value per Share	14.81	15.17
Outstanding, Weighted Average Grant-date fair- value per Share, Ending Balance	$ 14.82	$ 15.10

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

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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.

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

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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 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.

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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 price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

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The number of shares reserved for issuance pertaining to the outstanding stock options as of the balance sheet date for all option plans in the customized range of exercise prices.

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Number of options vested.

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The weighted average price as of the balance sheet date at which grantees could acquire the underlying shares with respect to all outstanding stock options which are in the customized range of exercise prices.

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

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