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Summary of Combined Activity Under Equity Incentive Plans (Details) - $ / shares | 12 Months Ended
--- | ---
Sep. 30, 2019 | Sep. 30, 2018
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |
Outstanding, Number of Nonqualified Options, Beginning Balance | 190,100 | 201,800
Exercised, Number of Nonqualified Options Outstanding | (24,500) | (7,700)
Forfeited, Number of Nonqualified Options Outstanding |  | (4,000)
Vested, Number of Nonqualified Options Outstanding | 0 | 0
Outstanding, Number of Nonqualified Options, Ending Balance | 165,600 | 190,100
Options, Outstanding, Weighted Average Exercise Price per Share, Beginning Balance | $ 17.81 | $ 17.47
Exercised, Weighted Average Exercise Price per Share | 8.78 | 8.78
Forfeited, Weighted Average Exercise Price per Share |  | 17.63
Options, Outstanding, Weighted Average Exercise Price per Share, Ending Balance | $ 19.15 | $ 17.81
Restricted Stock Awards (RSAs) |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |
Options, Number of Restricted Stock Awards, Beginning Balance | 327,225 | 288,800
Granted, Number of Restricted Stock Awards | 8,000 | 176,450
Forfeited, Number of Restricted Stock Awards | (2,875) | (21,925)
Vested, Number of Restricted Stock Awards | (111,938) | (116,100)
Options, Number of Restricted Stock Awards, Ending Balance | 220,412 | 327,225
Outstanding, Weighted Average Grant-date fair- value per Share, Beginning Balance | $ 16.42 | $ 28.92
Granted, Weighted Average Grant-date fair- value per Share | 14.59 | 15.13
Forfeited, Weighted Average Grant-date fair- value per Share | 14.60 | 18.75
Vested, Weighted Average Grant-date fair- value per Share | 16.18 | 45.19
Outstanding, Weighted Average Grant-date fair- value per Share, Ending Balance | $ 16.50 | $ 16.42
Restricted Stock Units (RSUs) |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |
Granted, Number of Restricted Stock Awards | 161,800 |
Exercised, Number of Restricted Stock Awards | (500) |
Forfeited, Number of Restricted Stock Awards | (24,010) |
Options, Number of Restricted Stock Awards, Ending Balance | 137,290 |
Granted, Weighted Average Grant-date fair- value per Share | $ 15.17 |
Exercised, Weighted Average Grant-date fair- value per Share | 15.17 |
Forfeited, Weighted Average Grant-date fair- value per Share | 15.17 |
Outstanding, Weighted Average Grant-date fair- value per Share, Ending Balance | $ 15.17 |

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- Definition Share-based compensation arrangement by share-based payment award equity instruments other than options exercised in period. + References No definition available. + Details
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- Definition Share-based compensation arrangement by share-based payment award equity instruments other than options exercised in period weighted average grant date fair value. + References No definition available. + Details
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- Definition The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period. + References 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=116856206&loc=d3e5070-113901 + Details
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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 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)(2)(iii)(3) -URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901 + Details
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- Definition 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 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)(2)(iii)(1) -URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901 + Details
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- Definition 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). + References 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)(2)(iii)(1) -URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901 + Details
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- Definition 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. + References 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)(2)(i)-(ii) -URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901 + Details
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- Definition Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options. + References 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)(2)(i)-(ii) -URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901 + Details
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- Definition The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period. + References 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)(2)(iii)(2) -URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901 + Details
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- Definition 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. + References 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)(2)(iii)(2) -URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901 + Details
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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. + References No definition available. + Details
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- Definition 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. + References 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=116856206&loc=d3e5070-113901 + Details
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