Inventories - Summary of Inventories (Detail) - USD ($) $ in Thousands	Dec. 31, 2022	Sep. 30, 2022
Inventory [Line Items]
Inventories	$ 605,369	$ 454,359
Work-in-process	22,833	21,691
Raw materials	26,755	25,835
New and Used Boats, Motors, and Trailers [Member]
Inventory [Line Items]
Inventories	404,444	272,422
In Transit Inventory and Deposits [Member]
Inventory [Line Items]
Inventories	132,505	117,268
Parts, Accessories, and Other [Member]
Inventory [Line Items]
Inventories	$ 18,832	$ 17,143

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Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

+ References

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-Publisher FASB
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-SubTopic 10
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Amount before valuation and LIFO reserves of raw materials expected to be sold, or consumed within one year or operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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Amount before valuation and LIFO reserves of merchandise or goods in the production process expected to be completed within one year or operating cycle, if longer.

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