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.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 805
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479907/805-20-50-5

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Amount of gain (loss) from sale and disposal of integrated set of activities and assets capable of being conducted and managed for purpose of providing return in form of dividend, lower cost, or other economic benefit to investor, owner, member and participant.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 230
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 28
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482740/230-10-45-28

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 810
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481203/810-10-50-1B

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Term of lessee's operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (a)(3)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147478964/842-20-50-3

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- Definition

Represents the number of stores.

+ References

No definition available.

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Acquisitions and Dispositions - Dispositions (Details) $ in Thousands		12 Months Ended
	Sep. 30, 2023 USD ($) location	Sep. 30, 2023 USD ($) location	Sep. 30, 2022 USD ($)	Sep. 30, 2021 USD ($)
Business Acquisition [Line Items]
Pre-tax gain (loss) on sale of business		$ (750)	$ 0	$ 0
Number of retail locations \| location	98	98
Disposal Group, Disposed of by Sale, Not Discontinued Operations \| Roscioli Yachting Center
Business Acquisition [Line Items]
Term of contract	10 years	10 years
Dealerships \| Disposal Group, Disposed of by Sale, Not Discontinued Operations \| Roscioli Yachting Center
Business Acquisition [Line Items]
Pre-tax gain (loss) on sale of business	$ 200
Dealerships \| Disposal Group, Disposed of by Sale, Not Discontinued Operations \| Lookout Marine
Business Acquisition [Line Items]
Pre-tax gain (loss) on sale of business	$ (1,000)
Number of retail locations \| location	2	2