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Shareholders' Equity and Stock-Based Compensation - Additional Information (Detail) - shares |  | 12 Months Ended
--- | --- | ---
Nov. 01, 2021 | Sep. 30, 2022 | Sep. 30, 2021
Class of Stock [Line Items] |  |  |
Number of options, forfeited or cancelled | 30,000 |  |
Number of shares, options expired |  |  | 170,984
2009 Plan [Member] |  |  |
Class of Stock [Line Items] |  |  |
Shares available for granting |  | 0 | 0
Remaining contractual life on the options outstanding |  |  | 5 years
Number of options, forfeited or cancelled |  | 0 | 0
2009 Incentive Compensation Plan |  |  |
Class of Stock [Line Items] |  |  |
Share based payments, options, expiration date |  | Oct. 01, 2021 |
Common Stock [Member] | 2009 Plan [Member] | Share-based Compensation Award, Tranche One [Member] |  |  |
Class of Stock [Line Items] |  |  |
Number of shares, options expired |  |  | 125,984
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] |  |  |
Class of Stock [Line Items] |  |  |
Number of shares, options expired | 30,000 |  |
Class B Stock [Member] | 2009 Plan [Member] | Share-based Compensation Award, Tranche One [Member] |  |  |
Class of Stock [Line Items] |  |  |
Share based payments, options, expiration date |  |  | Sep. 30, 2021
Number of shares, options expired |  |  | 45,000
Class B Stock [Member] | 2009 Plan [Member] | Share-based Compensation Award, Tranche Two [Member] |  |  |
Class of Stock [Line Items] |  |  |
Share based payments, options, expiration date |  |  | Sep. 26, 2026
Number of shares, options expired |  |  | 30,000

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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 Date the equity-based award expires, in YYYY-MM-DD format. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a)(2) -URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901 + Details
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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. + 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 https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901 + Details
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- Definition Number of options or other stock instruments for which the right to exercise has lapsed under the terms of the plan agreements. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1)(iv)(04) -URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901 + 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://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1)(iv)(03) -URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901 + Details
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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 -Subparagraph (e)(1) -URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901 + Details
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