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Summary of Stock Options Outstanding and Exercisable (Details) - $ / shares | 12 Months Ended |  |
--- | --- | --- | ---
Sep. 30, 2021 | Sep. 30, 2020 | Sep. 30, 2019
Share Based Compensation Shares Authorized Under Stock Option Plans Exercise Price Range [Line Items] |  |  |
Options Outstanding Shares | 38,800 | 91,100 | 165,600
Options Outstanding Weighted Average Exercise Price | $ 21.42 | $ 17.66 | $ 19.15
Range One |  |  |
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 | 5 years 1 month 6 days |  |
Options Outstanding Weighted Average Exercise Price | $ 21.42 |  |

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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 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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