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

Share Based Compensation Shares Authorized Under Stock Option Plans Exercise.

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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.

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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

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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

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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

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