INVENTORIES, NET - Schedule of Inventory (Details) - USD ($) $ in Thousands	Jun. 25, 2021	Sep. 30, 2020
Inventory Disclosure [Abstract]
Purchased materials and manufactured parts, net	$ 70,894	$ 49,192
Work in process, net	33,803	24,113
Finished goods, net	136,325	125,790
Inventories, net	$ 241,022	$ 199,095

Inventory, Raw Materials And Purchased Parts, Net Of Valuation Reserves

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- Definition

Carrying amount, net of valuation reserves and adjustments, as of the balance sheet date of merchandise or goods held by the company that are readily available for sale.

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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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Carrying amount, net of reserves and adjustments, as of the balance sheet date of merchandise or goods which are partially completed. This inventory is generally comprised of raw materials, labor and factory overhead costs, which require further materials, labor and overhead to be converted into finished goods, and which generally require the use of estimates to determine percentage complete and pricing.

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