PROPERTY, PLANT AND EQUIPMENT, NET - Summary of Fixed Assets (Details) - USD ($) $ in Thousands	Jul. 02, 2021	Sep. 30, 2020
PROPERTY, PLANT AND EQUIPMENT, NET.
Land and improvements	$ 788	$ 788
Buildings and improvements	8,302	7,430
Buildings under finance lease	27,709	7,750
Machinery and equipment	39,182	34,095
Furniture and fixtures	8,824	8,113
Software	5,215	5,215
Construction in progress	10,302	6,079
Total property, plant and equipment, at cost	100,322	69,470
Accumulated depreciation	(49,517)	(45,883)
Property, plant and equipment, net	$ 50,805	$ 23,587

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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Amount before accumulated depreciation of building structures held for productive use including addition, improvement, or renovation to the structure, including, but not limited to, interior masonry, interior flooring, electrical, and plumbing.

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Amount before accumulated amortization of capitalized costs for computer software, including but not limited to, acquired and internally developed computer software.

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Amount of structure or a modification to a structure under construction. Includes recently completed structures or modifications to structures that have not been placed into service.

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Amount, before accumulated amortization, of right-of-use asset from finance lease.

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Amount before accumulated depreciation of equipment commonly used in offices and stores that have no permanent connection to the structure of a building or utilities. Examples include, but are not limited to, desks, chairs, tables, and bookcases.

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Amount before accumulated deprecation and depletion of real estate held for productive use and additions or improvements to real estate held for productive use, examples include, but are not limited to, walkways, driveways, fences, and parking lots. Excludes land held for sale.

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Amount before accumulated depreciation of tangible personal property used to produce goods and services, including, but is not limited to, tools, dies and molds, computer and office equipment.

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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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