Inventories - Summary of Inventories (Detail) - USD ($) $ in Thousands	Jun. 30, 2025	Sep. 30, 2024
Inventory [Line Items]
Inventories	$ 906,219	$ 906,641
Work-in-process	18,090	24,996
Raw materials	16,052	22,454
New and Used Boats, Motors, and Trailers [Member]
Inventory [Line Items]
Inventories	805,226	784,152
In Transit Inventory and Deposits [Member]
Inventory [Line Items]
Inventories	53,441	60,470
Parts, Accessories, and Other [Member]
Inventory [Line Items]
Inventories	$ 13,410	$ 14,569

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No definition available.

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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.

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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

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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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