Right of holders to elect company's board of directors.

No definition available.

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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

Date the equity-based award expires, in YYYY-MM-DD format.

+ 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 (a)(2)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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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=120381028&loc=d3e5070-113901

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- Definition

Gross number of share options (or share units) granted during the period.

+ References

No definition available.

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- Definition

Number of options outstanding, including both vested and non-vested 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
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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-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

Weighted average remaining contractual term for option awards outstanding, 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
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-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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Shareholders' Equity and Stock-Based Compensation - Additional Information (Detail) - shares	12 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2019
Class of Stock [Line Items]
Number of shares, options outstanding	30,000	252,492	272,492
2009 Plan [Member]
Class of Stock [Line Items]
Common stock options issued to employees	0
Shares available for granting	0
Remaining contractual life on the options outstanding	5 years
Number of options, forfeited or cancelled	0
Common Stock [Member]
Class of Stock [Line Items]
Right of holders to elect company's board of directors	25.00%
Class B Stock [Member]
Class of Stock [Line Items]
Right of holders to elect company's board of directors	75.00%
Class B Stock [Member] \| 2009 Plan [Member] \| Share-based Compensation Award, Tranche One [Member]
Class of Stock [Line Items]
Number of shares, options outstanding	45,000	45,000
Share based payments, options, expiration date	Sep. 30, 2021	Sep. 30, 2021
Class B Stock [Member] \| 2009 Plan [Member] \| Share-based Compensation Award, Tranche Two [Member]
Class of Stock [Line Items]
Number of shares, options outstanding	30,000	30,000
Share based payments, options, expiration date	Sep. 26, 2026	Sep. 26, 2026