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Summary of Stock Options Outstanding and Exercisable (Details) - $ / shares | 12 Months Ended |  |
--- | --- | --- | ---
Sep. 30, 2020 | Sep. 30, 2019 | Sep. 30, 2018
Share Based Compensation Shares Authorized Under Stock Option Plans Exercise Price Range [Line Items] |  |  |
Options Outstanding Shares | 91,100 | 165,600 | 190,100
Options Outstanding, Weighted Average Remaining Term | 5 years 6 months |  |
Options Outstanding Weighted Average Exercise Price | $ 17.66 | $ 19.15 | $ 17.81
Range One |  |  |
Share Based Compensation Shares Authorized Under Stock Option Plans Exercise Price Range [Line Items] |  |  |
Range of Exercise Prices | $ 14.87 |  |
Options Outstanding Shares | 52,300 |  |
Options Outstanding, Weighted Average Remaining Term | 5 years 1 month 6 days |  |
Options Outstanding Weighted Average Exercise Price | $ 14.87 |  |
Range Two |  |  |
Share Based Compensation Shares Authorized Under Stock Option Plans Exercise Price Range [Line Items] |  |  |
Range of Exercise Prices | $ 21.42 |  |
Options Outstanding Shares | 38,800 |  |
Options Outstanding, Weighted Average Remaining Term | 6 years 1 month 6 days |  |
Options Outstanding Weighted Average Exercise Price | $ 21.42 |  |

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- Definition 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. + 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)(i)-(ii) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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- Definition 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. + 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)(i)-(ii) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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- Definition Weighted average remaining contractual term of outstanding stock options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + 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 (e)(1) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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